Just add points? What UX can (and cannot) learn from games is a great presentation by Sebastian Deterding examining the currently popular fallacy that adding points to a system is enough to make it into a game or enough to transform a website or service into something fun (something that has spawned some argument lately on Twitter, in fact).

I do think there is much for UX design to learn from games — and vice versa — but I also very much agree with the core thought here, which is that the two disciplines are different, and thinking that you can get by with a superficial understanding of one or the other is a mistake — they are not small disciplines!