....The way I read that is that you will still be limited to whatever data caps you have on your phone plan, even though the data is going over your own broadband connection(and not even Sprint's at that)....
It's my understanding that all the voice and data traffic will still route through Sprint (almost like a VPN since it's all encrypted). I can see this becoming popular in some households, so hopefully they'll find a way to make some allowances for femtocell usage.