I think APB will be a keeper in my house. My wife downloaded it on Friday and we played it together all weekend. We had a blast. Sure, we got our asses kicked more often than not, but we still got enough cash and prestige to make it worth our while.
The lag is a lot better than it was late in the closed beta, and they have clearly rebalanced the weapons to reduce some of the overall cheapness of certain guns. I loves my shotty.
I haven't even looked at the cash shop though. No idea what's up there.