Megadeth would be awesome, like badas* said Pantera would be cool but there not mainstream enough. I rekon they should release a game that includes songs from a whole genre not just from a band, say like GH: Heavy Metal or GH: Pop Rock. Just an idea.
Thats a hard question to answer for you... for me my favourite game is Gears of War 2 or possibly Fallout 3 but that's my opinion, i'm not sure what kinda games your into so to make it easier i'll list some good ones:
1) Gears 2
2) Fallout 3
4) Mass Effect
5) Halo 3
6) Fable II
7) Call of Duty Series (4 is the one to get)
8) Elder Scrolls IV: Oblivion
9) Resident Evil 5
10) Project Gotham Racing 4
Dude, why would you even ask such a stupid question?? It makes you look like an idiot, not to mention all the speling mistakes! i bet your one of those 13 year old kids that dribbles BS all day on halo until you get your behind strung up by a real player, like me. Go post somewhere else you n00b no one wants you here! ( thats my definition of a "troll" sorry for all the bad insults lol)
For May im mostly looking forward to UFC undisputed, just for a change. Not to mention thats about all that's worth anything. Screw Bionic Commando, i didn't like how the demo chucked you straight in there. Maybe the full game will deliver.