Our church has just started using Skydrive and so far we think it is great.  We are using a mix of MACs and PCs.  The PCs seem to be working flawlessly.  All three of our MACs show constant skydrive activity on the menu bar and if you click on the skydrive icon each of the MACs say they are download 2 files constantly.  They never get out of this state.  However, the sync functionality seems to be working.  Changes made to the directory tree on the PCs sync with the cloud and show up on the MAC local copy.  Changes made to the directory tree on the MACs sync with the cloud and show up on the PC local copy.  I have tried looking at the log files to figure out which two files the MAC client doesn't like, but I can't figure it out.  Perhaps these two files can be renamed or deleted and the problem will go away.