I've also got mixed feelings about Entertainer. While it would be awesome to have a game based on a traveling troupe of entertainers, I'm not sure how much fun it'd be just for one in a group. An entertainer would feel really out of place in most typical games I can think of that aren't specifically written with them in mind.
I've been playing an Entertainer in a game for the last five years, and she's an exceptionally deep and interesting character that I (and my fellow players) have never gotten tired of. And of course, it's not like she's capable of nothing but entertaining. If all the players enjoy roleplaying deep characters, an Entertainer can be just as fun and useful as everyone else. If the players are just a pack of 'murder hobos', however, then yeah, maybe not.