It is certainly important to note that a game should not be praised for simply copying something that its predecessor had (CoD style). Games need to be innovative and improve upon their design.
Now for remakes of games, this isn't really the case. Fans want remakes to be as faithful to the original experience as possible, all the while providing improved aspects and extras along the way. Anniversary does just this. While nearly all remakes up to now simply add HD textures and throw in some achievements, this game completely remastered the graphics to current gen statis (abliet not groundbreaking). Along with the graphics, they Also re-recorded the sound effects and OST with modern tech. Even if you prefer the retro feel, you can make both the score and visuals to the way they were 10 years ago quickly and whenever you want. Terminals are also put within the campaign to add extra immersion into the story, which will also drop hints at the upcoming Halo 4. Along with the remastered campaign, the game includes 6 new multiplayer maps and 1 new Firefight map for Halo: Reach multiplayer, something that goes above and beyond what is expected for a simple remake.
Though this is a 10 year old game, Anniversary provides more content and put in more effort than any remake of any game to date.