Stations that go to this one-artist-only format as a stunt generally are leading up to a format that plays that artist. There was an all-beatles station someplace that morphed into classic rock, and there was, in Fresno, I think, a "K-Garth" that morphed into Country. I can also remember an all Led-Zeppelin station that turned into a classic rock when that stunt was over.
I cannot recall any instance where a station stunted with all music by one artist, and then launched into a format that was completely unrelated. But, maybe someone in here can remember a situation where that happened.
On the basis of the Bruce choice, and the fact that this is Bonneville we're talkin' about, I would think this is going to be some kind of a drive-ish rock-based classic hits, since PPM arrives in LA fairly soon and PPM tends to favor rock formats.
AAA would be nice, though.