not sure date but it said they signed agreement saturday or something and that verizon said compatability between all carriers would be available around summer, google sprint verizon mms contract and you'll get a bunch of info att ,tmobile ,etc......... all the carriers are getting in on it ......
that's it the link above me good work buddy......I couldn't find it again lol!!! tkanks!!!!!!!!except now they have more updated articles as well