Halo: Anniversary is most definitely a game to buy this Spring for all gamers, particularly the old Halo veterans. With the fact that the gameplay is remained untouched (heck, with classic mode, you're experiencing the same game from 2001) although this time with the additions of achievements and a new co-op multiplayer system to make it all the better.
If you're a new player, now's your chance to travel back in time to discover how the extremely popular Halo series truly started out so that you may have a greater understanding of how the concept of Halo initiated. On the other side, if you're a Halo veteran (or just an average Halo player), you will undoubtedly enjoy this nostalgic experience from 10 years ago.
In addition to these wonderful factors, with a price this low, there's virtually no reason whatsoever for you to not buy this game.