I didn't see this posted anywhere else, so I thought I would share this info. If you could care less about achievements, have never played the original Rainbow Six: Vegas, or if you have already loaded this game onto your profile (ie. put it in your Xbox 360), then you can go ahead and ignore this thread.

Unfortunately Ubisoft has accidentally glitched one of their achievements by rewarding those that completed the previous RB6V on realistic difficulty and/or reached the rank of elite. The 'prize pack' that they provide, automatically promotes you to the rank of Specialist, along with giving you some extra XP and gear. Normally this would be a good thing, but this promotion forces the player to skip the rank of Private First Class, which turns out to be an achievement. The odd thing is, is that this glitch seems to affect ANYONE who has played the previous Rainbow Six, and not just those that have reached the 'prize pack' specifications.

In conclusion, if you have played the previous Rainbow Six: Vegas, and still want one of the easiest achievements in the game, then I would suggest you follow the instructions in the link below.

http://www.achieve360points.com/forums/showthread.php?t=75691

Spoiler warning. XBOX.com has a listing showing the achievements available in HALO 3. There are not any major spoilers in there. In fact everything mentioned in the achievement list has been discussed on the THX website before. If knowing things like the number of missions in the campaign bothers you, then quit out now.

by Hilary Goldstein at IGN

June 19, 2007 - Multiple Xbox 360 achievement sites posted the hottest list on this or any other planet today. Halo 3's 49 achievements (for a total of 1000 Gamerpoints) were revealed by achieve360points.com, among others.

A few things can be gathered from the achievements (oddly enough, none of which are secret). For one thing, these aren't final. At least, the descriptors are not, because some of the achievements have placeholders on scoring requirements. We also now know there are nine chapters in the campaign. And the skulls are back. In Halo 2, a skull was hidden in almost every level. Finding it was sometimes tough. Sometimes a skull in Halo 2 unlocked abilities; now it unlocks achievements.

When asked to confirm the validity of the list, a Microsoft representative said: "Halo 3 is still in development and achievements are not final."

Name Description Points
1. Landfall - Finish the first mission of the Campaign on Normal, Heroic, or Legendary. 20 Points
2. Holdout - Finish the second mission of the Campaign on Normal, Heroic, or Legendary. 20 Points
3. The Road - Finish the third mission of the Campaign on Normal, Heroic, or Legendary. 20 Points
4. Assault - Finish the fourth mission of the Campaign on Normal, Heroic, or Legendary. 30 Points
5. Cleansing - Finish the fifth mission of the Campaign on Normal, Heroic, or Legendary. 30 Points
6. Refuge - Finish the sixth mission of the Campaign on Normal, Heroic, or Legendary. 30 Points
7. Last Stand - Finish the seventh mission of the Campaign on Normal, Heroic, or Legendary. 40 Points
8. The Key - Finish the eighth mission of the Campaign on Normal, Heroic, or Legendary. 40 Points
9. Return - Finish the final mission of the Campaign on Normal, Heroic, or Legendary. 50 Points
10. Campaign Complete: Normal - Finish the Campaign on Normal. 125 Points
11. Campaign Complete: Heroic - Finish the Campaign on Heroic (unlocks achievement for Normal, if not earned). 125 Points
12. Campaign Complete: Legendary - Finish the Campaign on Legendary (unlocks achievements for Normal and Heroic, if not earned). 125 Points
13. Iron - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. - 10 Points
14. Black Eye - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
15. Tough Luck - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
16. Catch - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
17. Fog - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
18. Famine - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
19. Thunderstorm - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
20. Tilt - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
21. Mythic - Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull. 10 Points
22. Spartan Program Recruit - Win your first game in matchmaking to sign up for the Spartan Program (Online). 10 Points
23. UNSC Spartan - Earn your Sergeant rating to be recognized as a true Spartan (Online). 15 Points
24. Spartan Officer - Advance to the Spartan Officer ranks (Online). 25 Points
25. Two for One - Score a Double Kill with a single spartan laser shot in a ranked free for all playlist (Online). 5 Points
26. Too Close to the Sun - Destroy an enemy banshee with the spartan laser or missile pod in a ranked playlist or in campaign. 5 Points
27. Triple Kill - Kill 3 enemies within 4 seconds of one another in a ranked free for all playlist (Online). 5 Points
28. Overkill - Kill 4 enemies within 4 seconds of one another in a ranked free for all playlist (Online). 5 Points
29. Lee R Wilson Memorial - Score 5 grenade sticks in any ranked free for all playlist (Online). 5 Points
30. We're in for some Chop - Destroy an enemy vehicle with equipment in a ranked playlist or in campaign. 5 Points
31. Killing Frenzy - Kill 10 enemies without dying in any ranked free for all playlist (Online). 5 Points
32. Steppin' Razor - Score a Triple Kill with the sword in a ranked free for all playlist (Online). 5 Points
33. Mongoose Mowdown - Splatter an enemy with the mongoose in a ranked free for all playlist (Online). 5 Points
34. Up Close and Personal - Kill 5 enemies by melee or assassination in a ranked free for all playlist (Online). 5 Points
35. Fear the Pink Mist - Kill 5 enemies with the needler in a ranked free for all playlist or in campaign. 5 Points
36. Headshot Honcho - Kill 10 enemies with headshots in a ranked free for all playlist or in campaign. 5 Points
37. Used Car Salesman - Destroy a vehicle that has three enemies in it in a ranked playlist or in campaign. 5 Points
38. Marathon Man - Locate and access all Terminals in the Campaign. 40 Points
39. MVP - Earn the MVP in any ranked playlist (Online). 5 Points
40. Maybe Next Time Buddy - Board the same vehicle within 10 seconds after being boarded in any free for all playlist (Online). 5 Points
41. Demon - Score over X Points in the Campaign meta-game on the second mission. 10 Points
42. Guerilla - Score over X Points in the Campaign meta-game on the first mission. 10 Points
43. Cavalier - Score over X Points in the Campaign meta-game on the third mission. 10 Points
44. Askar - Score over X Points in the Campaign meta-game on the fourth mission. 10 Points
45. Exterminator - Score over X Points in the Campaign meta-game on the fifth mission. 10 Points
46. Ranger - Score over X Points in the Campaign meta-game on the sixth mission. 10 Points
47. Vanguard - Score over X Points in the Campaign meta-game on the seventh mission. 10 Points
48. Orpheus - Score over X Points in the Campaign meta-game on eighth mission. 10 Points
49. Reclaimer - Score over X Points in the Campaign meta-game on the final mission. 10 Points

Source = http://xbox360.ign.com/articles/797/797773p1.html

You can see the list with achievement images at Xbox360Achievements.org

Something new and exciting is happening to the way you experience games. On February 12, Xbox® is teaming up with Old Spice to bring you Xbox Rewards and the Old Spice Experience Challenge.

Xbox Rewards offers casual and hardcore gamers alike the chance to earn actual rewards for doing what they enjoy—playing games, earning achievements, and having fun. Xbox Rewards is a free program, but in order to register you will need to have a valid Windows Live™ ID with your Xbox Live® gamercard linked.

The program is launching in the U.S. only, and you must be 13 years or older to participate.

Microsoft has issued some new guidelines that are sure to impact us soon. The good news is that we can earn more Gamescore points per game. The bad news is that the game developers can control WHEN they make all the Gamerscore points available and 1000-1250 total points might not be available on the retail disc. From Microsoft:

1. All regular disc-based games MUST have 1,000 Gamerscore in the base game. This means that any consumer who buys a retail game will have the opportunity to unlock the full 1,000 Gamerscore without having to pay for any add-on content. Note that a publisher may decide to deliver a portion of this Gamerscore via add-on content, but the add-on content will always be free to the consumer.

2. Game publishers will have the option to deliver another 250 incremental Gamerscore on top of the 1,000 via add-on content from Marketplace. This add-on content could be either free or paid. So if you complete a game and earn the full 1,000 GS, you could by getting new add-on content earn up to a total of 1,250 points from a game.

3. Xbox Live Arcade games will operate in similar fashion, but given the size of these titles they will allow you to earn up to 200 Gamerscore from every game and up to another 50 points from add-on content.

“A perfect example of this is the recent release of Crackdown, which has delivered 900 Gamerscore today on the retail game disc. The remaining Gamerscore in Crackdown will be made available, for free, via a future content update. A number of the title's future Achievements will likely be based on some of the amazing feats executed through the streets of Pacific City, as well as the exciting additional content that Realtime Worlds currently has up its sleeve.” – MS’s Gamerscore blog

That sounded weird at first. So, I reverted back to guideline #1 and TFA. It looks like you are guaranteed the opportunity to unlock 1000 Gamerscore points on all retail games without having to pay extra. But, the 1000 Gamerscore points don’t have to be available on the disc. They just have to be offered for free at a later time via downloaded add-ons from the Marketplace. So, Crackdown will have 100 Gamerscore points hanging out there as a free add-on made available after the release.