If anyone is curious if the new plans would save them any money or not, just factor the plan as though you were under contract, add $25 per line, and see if thats less than what your paying now.
Right now I have 9 Lines and pay $360 a month, if I were to switch to these new plans it would drop to $235, a savings of $125. However with my current set up I get 9 upgrades a year, so if I were to say do the same and upgrade those lines with the new plan, i would be paying $460, an increase of $100 dollars a month.
Also, the at&t next isn't quite as bad now as everyone is making it out. Remember when you trade the phone in you still owe on the phone, so it would be the same as selling your old one to subsidize the new one. So lets say you get an iPhone, at&t's website is showing that is $32.50 per month for 12 months, thats $650 when you pay it off, same as if you buy outright. Now if at the 12 month mark you decide to trade in your phone for a new one, that means you still had 8 months of payments left, which at $32.50 a month would be $260. So if getting the extra $40-$140 by going through ebay or craigslist is worth it to you your better off selling and buying yourself, but if you don't want to deal with that, your basically only losing out $100 a year to not deal with that.