The game I am playing the most this week is Guitar Hero III. The first day I had it I played through 23 out of the 42 songs on career mode. I would not recommend doing that again as my hand is still numb.
I have to say that the Les Paul wireless guitar is a definite upgrade to the initial Xplorer version. WIth detachable faceplates you can change the look on the fly (Sold Separately). But the most impressive thing about the guitar is the feel. It is very natural with the button placement and just feels right. Being wireless is good as well as when you are thrashing about the living room you don’t pull your Xbox onto the floor.
There are some great songs including the Rolling Stones “Paint it Black” and one thing I was not sure about initially was the battle mode. As you progress through the career you encouter different “legends” such as Tom Morello from Rage Against the Machine and Slash of GnR and Velvet Revolver fame. This is also the basis of some of the competition via Xbox Live. Although watch out for the sudden death showdowns if you tie during a battle. Miss a single note and you could be done.
All in all I would recommend GH 3. It is still a fun game with new tracks and a new guitar and having Live access for career co-op or battles is great as that was definitely missing from GH 2.
Other games I am into right now are still Halo 3 and The Orange Box.