I've been listening to a fair amount of live-play sessions of Eclipse Phase recently. For the record and the curious, this has all been courtesy of the Role-Playing Public Radio and Technical Difficulties podcasts. I like the exceptionally novel ideas that are inherent to EP -- the kind of plot complications and ethical dilemmas that you just don't find in any other RPG and that are part-and-parcel of a transhumanist setting, where the spectrum of sentience is really wide and physicalities are changed with the regularity of socks.
I enjoy the opportunities to listen in on groups playing this game, as I know I'll likely never do so myself. And this is fine -- there are lots of other RPGs I'd rather get to first anyway. Aside from matters of time vs. the fairly enormous queue of games that has already lined up in front of EP, a big hurdle for running/playing this game is the setting/universe and the built-in metaplot that goes with it.