Your list of most underrated titles this gen

[Barozi]

Too Human - Main story is a bit short for a WRPG, but just like Mass Effect, there are many reasons to come back. Played it for about 40 hours and was a very enjoyable game. I especially loved the fighting mechanics and the amount of weapons. Attacking with the right analog stick worked like a charm. It also has some brilliant achievements.

50 Cent Blood on the Sand - VERY enjoyable arcadey TPS (With co-op feature). Hilarious bland story (I consider that as good ), but simply great gameplay.

Amped 3 - Surely not as good as the old ones, but this is like a good Tony Hawk game only on a snowboard. A must have for every THPS, Underground, Project 8 fan.

Resistance 2 - One of the best FPS of this generation. Almost as good as Call of Duty 4. Brilliant singleplayer with awesome boss fights, great art style and lots of different locations.
Very good multiplayer with lots of other players and nice online co-op.
Only splitscreen co-op is missing in this game.

Assassin's Creed - contains almost all gameplay elements from the undoubtedly superior 2nd game, but has a small flaw. It's repetitive. But as long as the gameplay is fantastic I want more of this repetitiveness.

Blue Dragon - Awesome JRPG with one of the best turn based fighting systems I've ever seen. Fantastic art style. Only downers are the annoying characters......and maybe the rather bad achievements.

Dante's Inferno - It's no God of War, but it has good gameplay and that is all what counts. Oh and if you like virtual tits make sure to buy it.

MagnaCarta II - If you've played all the popular JRPGs of this gen and still want a new one, but refuse to buy Enchanted Arms, The Last Remnant or Infinite Undiscovery, then get MagnaCarta II.
Also a very enjoable game that doesn't get too much attention unfortunately.

Ninja Blade - Tons of fun, stylish and simply great. At least in the same league as Devil May Cry 4 or Darksiders.

Robert Ludlum's The Bourne Conspiracy - I haven't even seen the movies and I liked what I played. Should be cheap by now and definitely worth a playthrough. Must have for a fan of the movies.

The Darkness - FPS with one of the groundbreaking stories of this gen (still talking about shooters). But don't let the abbreviation FPS fool you. It's far more than that.

Condemned Criminal Origins - One of the best horror games ever made. Great fighting mechanics.

Tony Hawk's Project 8 - Every true Tony Hawk fan should own this. In the same league as the best Tony Hawk games.

Crackdown and Lost Odyssey are obvious choices as well.
I also agree with Dark Messiah of Might & Magic and Star Wars The Force Unleashed.