I've been fighting with my image hosting account, so I'm getting caught up on replying to the last two pages of this thread.
Specifically...
When considering "who's a douche?" we need to agree on some kind of talent vs ego ratio. Consider Prince. He strutted, he sassed, and (at least in the person he presented publicly), he was a self-absorbed narcissist with an ego the size of Cleveland. But he was also among the most musically gifted writers, performers, singers, and instrumentalists of the last 50 years.
Thus, (read this in your Maury Povich voice), "Prince, you are NOT a douche."
Lots of rock stars in that group, I'd argue. Jimmy Page, Elton John, Chuck Berry. They might have been arrogant assholes, especially at the height of their stardom (though two of those three examples found contrition and humility in their later decades). But I don't think that being an asshole is the same thing as being a douche.
It's like Dizzy Dean said: "It ain't bragging if you can do it."
Lindsey Buckingham is a unique rock guitarist and a phenomenal talent who wrote and produced brilliant music. Not a douche. I will die on this hill.
So where should we draw the line? Neil Schon ("You ARE a douche.")