Anyone on the TAP program or some super-elite special relationships with Microsoft (e.g. 1000s of licenses of MSDN), now is the time to play your cards. Contact Microsoft and make it clear to them that you are not going to touch this product for years to come.
A big thank you to the supporters so far!
I don't think you can be in the TAP program and still be running on XP, that would kind of defeat the point, wouldn't it?
In any case, if you've only got 1000 people who actually care, I'd say you've pretty much confirmed that Microsoft are right not to worry about it.