It may be overhyped but its still full of epic win. I've only begun to play it (halfway through campaign), and its challenging even on Normal in campaign. But that's mostly because I'm terrible at FPS games.
Graphics are epic, action is awesome, cinema is great, its more challenging (but not as much as the first Halo was) - just get the game already!
You're going to love the Sabre level...
Please feed the trolls. XD