I foresee Apple promoting the fact that when buying songs from iTMS, that the songs can be used as ringtones on the iFone. I don't see Apple selling another ringtone format. Heck, you can purchase the whole song for $.99.
But, here is a twist on the iFone - you can set a playlist to be your ringtone list and it will shuffle between them!
I think I see where you are going with the rename of iTMS since it will be the hub for music, movies, tv shows and phone integration, but I don't think iLife will be it since they have that already used. iTunes Media Store? Much like they have the iPod brand, I don't see them ditching on the iTunes brand either.