By now, you've probably heard of a new game by Bungie that promised to merge Borderlands, Mass Effect, and Halo into one magical gaming experience; then you probably heard about how pissed people were when this didn't come close to being accurate. As a result, the game became fairly polarizing and reviewers were divided into two camps: Lovers and Haters.
I'm a lover.
This game isn't a massive multiplayer online (MMO) game anymore than Diablo 3 is; it is simply a Halo reboot with next generation graphics and a loot treadmill. It doesn't do half of what the pre-release hype said it would, but what it does, it does extremely well.
All in all, the game is a fantastic first person shooter. It combines just enough character progression to make the repetition feel satisfactory with the fast paced action that will keep you on the edge of your seat; but if you already have an addictive first person shooter (or you hated Halo), then you may want to hold off on purchasing this game until they flesh out some of the features in future updates.