I'm not a member of AICPA or my state's CPA society, so can't really answer directly, but there was a huge thread (IIRC it turned into a bit of a fight) on this topic awhile back, and basically what it came down to is the proponents of joining the AICPA said you should join since they're fighting to protect the industry, and the proponents of the state societies said they make more sense since they're local and your dues are going back to your area.
My conclusion? The state CPA society is mostly in the big cities, about 2 hours away from me, so there's no point in joining it for networking, even if I was looking for that. Getting the free magazine from either isn't worth it, and I'm not trying to market myself (aka in public accounting marketing to customers) in a way that “Member of AICPA” will matter to anyone. So…no purpose to paying the dues.
Now…if I was in public accounting, especially if I was a sole proprietor or part of a small firm, I'd probably join for the “clout”, since customers may not realize that the only requirement (to my memory) for joining the AICPA is to pay their bill. But, in private, where no one will care and if I'm looking for a new job they'll know how the AICPA works, I see no purpose to it. And…with all the state events being far away and not applicable, I haven't spent the money to join.