There's still shops who have a MFC codebase who cant just throw it away since its well tested projects and for those it can be useful but as a learning exercise it would be better to learn straight Win32 programming from which MFC and .NET still is derived.
From my experience:
Guerilla games the makers of the PS3 Killzone series have tools in MFC
Bosch security systems where I worked still use MFC
Philips medical still has.
For new development they all use different technologies though.
