so, this is out now and the big question, is MP worth the shortened dev cycle? kotaku basically called this a OMD 1.5 but was all right with it.
The multi-play adds alot to the game especially if you are co-oping with friends (which you sort of have to do since there seems to be no lobby). The addition of the Sorceress is very complimentary (new skills and abilities) rather than just having a second character on the map. The difficulty seems to have been ramped up quite a bit IMHO. I played the first Orcs and had no problem whatsoever 4 and even 5 skulling my way through the first 10 or so maps while I am already stalled on map 6 of Orcs 2 (I can complete the map but so far not without loosing Rift points) and co-op ups the difficulty even another notch. The dev's went above and beyond in adding more depth to the game with tons of new traps, weapons, trinkets and loads of upgrades for each.
I did encounter some bugs with the game, constant crashing on one particular map, Orcs getting stuck and being unhittable so you cannot complete a map and targeting seems off somehow, I've missed an Orc firing from point blank range right in its face.
My only real issue with the game is I have been playing alot of Dungeon Defenders lately and it's hard not to bias my opinion and I personally think Orcs and Orcs 2 falls short. Particuarly in the "walls" aspect. Proper wall type usage and wall placement to funnel creatures is a huge part of the strategy in Dungeon Defenders and mostly non-existant in Orcs 2. You have access to barricades but they are extremely cost prohibitive and a single hit from a couple of Kobold Sappers will wipe out all your walls and the game likes sending Sappers out 6 to 8 at a time.
The OMD games definitely have a more player involved and visceral playstyle but if you enjoyed the first game I'd say you will like the second and co-op can be alot of fun.