Q: 10.6.7 and XSAN 2.2.1

Not yet. We are still on 10.6.4 as each new update has had some sort of significant issue. These things don't directly effect the function of an MDC, but since your clients have to run an equivalent version of OS X or older, we haven't recommended that any of our clients update their MDCs to accomodate an OS update on their client machines.

10.6.5, Wifi:  https://discussions.apple.com/thread/2644274?start=0&tstart=0

10.6.6, FCP/ ProKit6: http://www.digitalrebellion.com/blog/posts/mac_os_x_10.6.6_breaking_final_cut_st udio.html

10.6.7, Fonts in FCP: https://discussions.apple.com/thread/2792142?start=30&tstart=0

JM