It does seem like the T-abyss virus could be in RE6 though because everyone says that there was a 6 in the tube. Maybe the C-virus was somewhat made by T-abyss. I agree that all of these new virus are getting a little out've hand. Capcom needs to stick with one virus for awhile and then create and new one.
It's hard to believe that the ending of Revelations could be ignored, or unless Capcom plans on making a sequel to Revelations. Regarding the very first trailer for RE6, I know Capcom confirmed it was fake, but I was reading around and everyone says that Capcom now confirmed that the trailer is actually real. I guess they said it was fake because the public was never meant to see that trailer. If it is infact real, that means Veltro will be in RE6. Jessica was last seen reading Dante, which had a heavy influence on Veltro. Maybe Jessica's taking over?