Is it "Always Sunny in Philadelphia"?

Any fans of this show out there? How come I just found out about it? I had pretty much given up on sitcoms after Seinfeld went off the air. I happened to stumble upon this show a couple of weeks ago on the FX network. How long has this been on the air? What I've seen so far has been pretty entertaining, with a level of sophistication to the humor than you normally don't find these days on network tv (No cute kids, no smart wife with bumbling husband). I need to see more of this ...