woohoo! CM9 is coming to the thunderbolt officially! it was confirmed in this Q & A session with Cyanogenmod
https://docs.google.com/document/d/1DFgHAi7-xkXiRdU5S6WXsqx26lzmiI60tntQhqsz6Js/edit?pli=1
https://docs.google.com/document/d/1DFgHAi7-xkXiRdU5S6WXsqx26lzmiI60tntQhqsz6Js/edit?pli=1