I used to have a stock answer for people who asked me whether they should use MFC to build Windows CE applications: Don't do it! The old Windows CE systems with their slow CPUs were hard-pressed to run complex, full-featured MFC applications. These days, I'm a little less dogmatic. The newest Windows CE platforms are now fast enough to allow MFC-based applications to run with reasonable performance. The MFC runtime library is included in ROM on these devices, so the footprint of the application is simply the code, not the code plus the MFC runtime.
But just as speed and the runtime have been added to the platforms, the sun is setting on MFC. Microsoft no longer pushes development of MFC applications. Instead, the .NET environment is the development target of choice. So should you develop in MFC? I say no, not for new projects. For old ones, there still is a place for MFC simply so that the projects don't have to be ported to other tools.