I have had the pleasure to meet Cliff many times during my career as a developer. First time I met him was at GDC 07, kind of a fanboy moment. But subsequent meet ups at different trade shows or E3 parties were more professional talking about games, life, and G1 Transformers. Most recently I met up with him at our Borderlands 2 party not too long ago.
Indeed people talk crap about him but overall he is a super nice guy and smart as hell when it comes to talking about game design. Truly a legend and inspiration for many up and coming designers of the guy who made games and levels and went pro doing it. If he can do it you can do it was something I admired about Cliff. Sure he made it really pro (lambo money) but the idea and concept was there.
Overall, I think Cliff has always been very approachable even back in the UT mod days where I would send him an email asking for feedback and actually get an email in reply of how to improve a level.
Anyways, weird things have been going on at Epic or perhaps it is all circumstance that Rod, Lee (and six other guys like Demond and Mikey) and now Cliff have left Epic.
Looking forward to see what he does next, and hopefully meet up with him again at a future industry event.