Cliff - I don't remember how I heard, but I'm guessing on the radio (KNAC).  I was worried the band would fall apart.  I was lucky enough to see him play.  They opened for Ozzy at Long Beach arena.  I was also lucky enough to see Randy Rhoads play.  Yes I know, I'm an old fart.
Rick - I don't remember how I heard, but again probably on KNAC.  Once again I was lucky enough to see them play when he had two arms.  I was glad to see they kept him.
Challenger - That I remember, I was entering my class at school (a flying class - what a bizarre coincidence) when the class mentioned it.  After class I was looking for tv's to see the footage, then seeing it played over and over.