on irc IIRC, or via email, when I payed him the 100 bucks for winning this cup. Of course that doesn't mean it's the reason for dissapearing. On the other side, he was one of the few pros on that level who still played for fun so who knows.
jibo has had the reputation for being one of the most dedicated players come tourney time, some russian players made rather snide comments on his attitude back then.
how do you know the other 'pros' do not enjoy playing quake (anymore), did you ask them one after another? i'm slightly confused.