I was playing this with a co-worker last night for a couple of hours. Its worth the download. The controls are a little awkward at first (at least for me), but after you get comfortable its pretty fun. It reminds me quite a bit of the Diablo games, but with the match-making co-op style of play from L4D(2).
We should come up with a time to get four people together.. Tess and I tried and AI doesn't control the missing party members. Also without any instructions those hacking mini games the tech class get are fucking difficult.
Edit: We got a third and it went much better. Got three or four levels in before Tess had to go to bed.