September 7, 2009 -- 

Mac OS X 10.6 Snow Leopard appears to break the Screen Sharing application for Bonjour, Back to My Mac, and direct connections by displaying a black or frozen screen on connection. However, I've discovered any easy fix. From the View menu, choose either Full Quality or Adaptive Quality, whichever item isn't checked. This allows screen sharing to flow again. I imagine that Apple will fix this problem in a minor update soon. [According to Glenn, the problem appears to have been fixed in 10.6.2. —Tonya]

—Glenn Fleishman