Well, I loved the campaign, and horde is fun, but only for so long in my opinion. I really hated the multiplayer. Tried is numerous times, and it never got better. It was really laggy, slow to even find a group of people, and just not fun. I'm not sure either, but most games I couldn't hear my team, which doesnt help.
It's fun and all but i wouldn't buy it, I just rented it and still really enjoyed it.