I'm also curious if the problem with missing SMB drives hanging the system has finally been quashed (it wasn't in earlier builds). Basically if an SMB share (CIFS, think "Windows share") is mounted and is unreachable, the system (most particularly the finder, but eventually the dock and other apps) just hang, sometimes for entire minutes, as timeouts occur. This is/was, well, less than robust and a huge problem for anyone using Macs in a Windows environment. Particularly a problem for corporate or portable users.