I'm hopeful. I guess it will depend on what sprint has in the pipeline. If there is an Evo 2, or Evo like device coming shortly after Gingerbread's release, I say no. But if we have to wait until June for another android super device from sprint, I say yes.
Also, if sprint starts waffling, with the number of Evos sold, if we pressure sprint enough, they just may do it.
Either way, if you are rooted, Gingerbread will be on your Evo....