I've figured out what my problem is with the Anny, and it has nothing to do with the fact that we may not be getting any classic Doctors either.
My problem is that if they're going to do a multi-Doctor story, just having two Doctors seems a tad on the dull side (regardless of who those two are). If Eccleston had agreed to do it and it was at least the three of them in the Special, I wouldn't be having this issue.
Maybe they'll call this one "The Previous Doctor".