the short focal flange distance and lack of mirror to bump into allows many more lenses to be adapted (using a purely mechanical adapter: you can bypass the focal flange distance incompatibility by using an adapter with built-in optics, but those are usually awful and will kill the IQ from your lens)

http://en.wikipedia.org/wiki/Flange_focal_distance
http://www.similaar.com/foto/lensmount/lensmount.html

So basically any lens that you can get to cover the sensor will work since you aren't dealing with the focal distances? Thanks for the links.

Any lens that can cover the sensor (i.e. the image circle is big enough) will work since you (most probably) aren't going to have flange-focal-length issues