I can't find it!?
+3
A:
ExportFactory<T>
is not part of MEF for the desktop (yet - as of now, it's only released for Silverlight). It looks like it will be included in MEF 2.
In the meantime, Glenn Block posted a version of the Composition.Initialization assembly ported to MEF for desktop development, and placed it on his SkyDrive. Alternatively, you can use the Preview 1 release of MEF2, which includes this.
Reed Copsey
2010-09-21 15:59:25