I wasn't a huge fan, I like my fantasy a little more serious in nature (he wrote satiric, whimsical fantasy - and lots of it), but I did respect his inventiveness and good humor. He'd probably be a lot more fun to have a beer with than would someone like GRR Martin. His books were likable even though they weren't exactly to my taste (I've read maybe 6 or 7).
Anyway, a great loss for the fantasy literature world.
http://www.bbc.com/news/entertainment-arts-31858156