Slash always seems to have something going on. I think Velvet Revolver is done though.
Personally, while I'll agree that the singer is definitely one of the biggest factors in a band, I don't quite agree that "anyone can play guitar." For example, Van Halen is named after it's guitarist... even if you have a preference of which singer they have. Pantera is a personal favorite and a great example. The late, great, guitarist, Dimebag Darrell was as much a part of that band's sound as frontman Phil Anselmo was. (I've heard Anselmo in other bands and although I like them, they just aren't the same.) Another one of my favorite bands, Demon Hunter, just recently got not one, but two new guitarists. The singer is still the same, and the music is similar, but it's still different to me.