I bought Deathspank last night not knowing much about it, just that it's an ARPG and I'm a loot junkie. As it turns out, it's a pretty hilarious game. Not many can get me actually laughing out loud. It's a bit simplistic for the genre, much like Torchlight, but the style is pretty neat, and the voice acting is top-notch, especially the guy who voices Deathspank. It's over-the-top and awesome.
As for the gameplay mechanics, it's different from normal conventions in that there's no spell tree; weapons have built-in spells, so you have to use a specific weapon to use a specific spell. The skill tree is done via Hero cards, which is an interesting twist. I'll have to play more to see if it works out in the end.