I personally don't think it's worth it. The discounts hotels and car rental companies will give you are available through other means (sometimes just by asking), and the maps and trip guides are not very useful now that most people have internet access. I guess if you drive an old clunker that's constantly breaking down then it may be worth it, but if you need one roadside assistance call every few years or so then it's probably better to just pay for the service yourself than get an AAA membership.
I would definitely have AAA or some other roadside assistance program if taking a cross-country road trip or something like that. But if you just drive mostly in your area, then towing is cheap and help is nearby, so there's no point.