Decent bit into Torchlight now... just finished Level 28. overall, I'm enjoying this game a lot. Not quite as good as 2, but still good.
My main complaint would be that it feels a bit uneven as far as difficulty is concerned. There are a lot of side maps to play through... and those serve to level you up well beyond what you get from the main dungeon.
However, the enemies in these side dungeon tend to be right around your current level, while you quickly pass up the enemies in the main dungeon. Last I saw, I was TWENTY levels above the enemies I was fighting in there.
However, as I mentioned, the enemies in the side dungeons mirror your level for the most part... and they are WAY tougher, especially enemies that do elemental damage. I got my ass handed to me by some guys using fire and poison in one of those dungeons, despite having fairly high numbers for all my resistances. In the main dungeons, I seldom feel threatened. It seems kind of out of whack to me... like the damage those guys were doing was disproportionate to everything else in the game.
I also had a couple incidents where equipment "disappeared". I'm not sure how it happened, but 2 or 3 times I would go into my inventory and notice gear missing from a slot. That is just a tad annoying. Since I don't know how/when it occurred, it could have been something I did or a bug... no clue.