winsupersite there is confirmation that the Nokia Lumia 900 is coming to AT&T on March 18, 2012. Plus that Verizon will get the Lumia 710 in April 2012.According to
There is also a rumor that these phone may ship out with Windows Phone Tango. Since there is no source on this story take it with a grain of salt. However it does make sense and this site has been dead on the mark on many other things. Plus the specific dates make me believe it more.
I Can’t wait for CES to see if it confirms or denies this!!