APB was a massively disappointing game. I was so upset with it -- the balance was terrible, I mean, I honestly have never played a game so poorly balanced. Two guns could get you through the game with no issues at all.
The character designers, built-in image manipulators, audio tools, stuff like that were all incredibly innovative and impressive, but the gameplay itself was really upsetting. Bob, Eagles, and I had fun for a bit with it... but we were ultimately left disappointed and felt like we had wasted our money when we got through our first 10-15 hours of play (which isn't a lot for an MMO).
I haven't followed it since its initial failure, I'm not sure if it's gotten balanced and fixed or not. The game was a great concept, but it was a classic case of poor execution. Let me know if you try it and find that it's still playable after 10-15 hours.