Its really nothing like Diablo except for the fact that you're killing demons and getting phat lewtz in random dungeons. Gameplay wise, its closer to a steampunk Oblivion except the maps and missions are akin to Guildwars. The skill system is pretty much identical to Titan quest except you only get one skill set.
All-in-all, I like it. I'm not overly fond of the summoner, but the Hunters are pretty cool. Melee characters get a grappler that drags enemies close to you and stuns them.
I just hit level 14 and act 3 last night. So far, acts 1 and 2 were more or less identical. Industrial basements, subway tracks, sewers and cityscape.
The guns are really interesting. Theres something like a shotgun that shoots bees that swarm. Theres a grenade launcher that shoots crystals that explode and launch a bug swarm. Theres a tenticle gun that shoots out 7 tenticles to choke people. Theres a lightning shotgun too; it shoots a ball of lightning that splits into a bunch of charges. Rocket launchers blanket the floor with a ring of flame that burns for a few seconds. Theres also a lava gun that sprays a get of napalm that ignites the ground. And a few dozen more.
[quote name='crystalklear64']Well, you're one of my diablo homies... how does this thing compare?[/quote]