Best Buy is opening new concept stores called Best Buy Mobile, "a new Best Buy concept focusing on sales of smartphones and mobile devices such as the iPad." Radio Shack is heavily into cellular and tablets, now carrying pre-paid from Boost, VZW, tracfone and one other plus the 4 post-paid carriers (ATT, VZW, T-Mobile and Sprint).
Cbeyond has had an MVNO for a while. XO just signed on as a Sprint MVNO.
Tech Data just signed a deal with Brightstar to basically become Radio Shack for VAR's. TDMobility is being messaged as a PAAS, but its an MVNO with Sprint, T-Mobile and ATT services being sold with devices through a portal that TD and Brightstar manage for the VAR (service provider) and the end-user.
Everyone is trying to figure out a mobile play.
Since MVNO plans have not worked out previously for so many companies (mainly due to a scale issue), I don't see how the new MVNO's will make it work either. You need 6K lines a year to break even!