I'm not that good at it either, but I still find it fun because of the characters involved. Losing doesn't feel so bad when it's Heavy Weapons Guy taking your chips and calling you a baby man. Of course, a lot of the game is luck too. Just by playing tonight, I picked up on a lot of the rules and card sets, though I still lost quite a bit due to taking risks and having bad luck, generally at the very end (I consistently make it to the 1-on-1).
I did win those sweet Shutter Shades for Demoman, though.