I think they got this message now after 4 years of not getting it. What I've heard is that Orcas will focus on some improvements in MFC to vastly improve the leveragability of both the XP and Vista user interface experiences - something I'm highly looking forward to, being an MFC programmer myself.

But what other classes do you want, other than being able to take advantage of new OS controls? Any non-UI related stuff you can suggest?

I think your point about open source has already come into fruition with WTL, some people didn't like the weight of MFC and wanted something a bit cleaner, but in a similar style as MFC, so WTL has survived and is still growing.