Yes, he of Bush fame. Oddly enough, he was in the tabloids here a few days ago, with this picture:
Apparently, he's not much of a clothes horse, because he was wearing those exact pants in the park. All in all, very nice dude and, yes, he loves Starbuck (I mean, who doesn't?). Although I have to question his choice of dog breed (he was walking a Pomeranian). My guess is that it's Gwen's.