I run a 2 room facility that has been "ready to go" to OS X for 9 months now. During those 9 months, we have been able to really stablize our OS 9 systems. We have (KNOCK ON A GREAT HUGE PIECE OF NICELY CARVERD OAK) not crashed in days on either machine (g4 1.25 dual boot MMD OS 9.2.2, PT 5.3.1 CS6, HD3). There is yet to be that "Killer Application" for us to move up. We manage files well, do decent routine maintenence, and keep abreast of things via the DUC, PTU.org, Musicplayer.com etc. All I keep hearing is that OS X rigs can be slower and that there are still serious issues depending on configs. If you're stable and working, why upgrade? When Digi gives me a feature that knocks my socks off AND can convince me that the -90XX errors and what not are a thing of the past, then I might consider it again.
Sorry for the long ramble,
PS. I'm not bashing Digidesign at all. I love their products and have never been happier with the sound, ease of use, palette and quality of 3rd party input, etc. I just think they and everyone else were forced to port to OS X too soon, and now they'll never catch up. But then again I'm just a user, not a computer head, so what do I know?