USA Today has recently published that Poison frontman Bret Michaels will be contributing to the game the following:
Talk Dirty to Me - Poison
Go That Far - Bret Michaels Band
In addition, it says that Michaels will be the vocalist for the tracks.
Personally, this is great news - Poison is as good as glam goes, and having another guy who's contributing nearly as much as Slash kind of takes the limelight off him.
Michaels isn't a lead guitarist, from what I recall. Which means the other guitarist is still up for grabs. But still, this is great news, real-life people that will be in the game are good.
But anyhow, yay Poison!