It's easy to bash CliffyB, but what I think will be interesting is to see is what Epic does post-CliffyB. Say what you want about him, but he delivered successful games for Epic for nearly 20 years. When the Unreal games took a nosedive was when he stopped working on them. Frankly I think that's why PC gamers hate him, above all else.
Annoyances about his personality aside, I'm not sure Epic has anyone that can fill his shoes. They have some solid artists and level builders, but I don't see any great designers. It's like id Software without John Romero around.