It is very, very unlikely that Microsoft would offer OSGi support in MEF or Unity.
OSGi is Java-based technology, and uses Java for its interface. This would be inappropriate for usage with MEF or Unity, since they are not designed to work on the Java platform, and have nothing to do with Java whatsoever.
Microsoft has many technologies that are .NET oriented meant to accomplish some of the same goals as OSGi, however.
Reed Copsey, Jr. -
http://reedcopsey.com