Yes, you still have a persistent pet that continues to die repeatedly. There are four very different classes from the first. The engineer and all his explosions are quite fun to play with.
Instead of being stuck in a mine you roam around the countryside murdering things. Then you go into mines and caves and junk.
The music for "Act 1" as I'll call it is very, very similar to Act 1 Diablo 2. Like, after one strand of notes on that mandolin/harp/stringy thingy, I half expected to see Blood Raven or Andariel followed around by a bunch of red imps and zombies.
Either way, I wouldn't put down everything to grab Torchlight 2, but if you're looking for a fun diversion I'd give it a shot. (Also I'm holding off on playing with Pandas, so there ya go.)