It appears that Blizzard has made some fairly major changes in the UI API code, so many of the addons in the UI aren't updated into a functional state yet. I have the UI back in a semi-working state, and as soon as I get everything back working with no errors, I'll publish a new version of the UI.
I get the impression that many of the mod developers didn't have much time to do testing on the PTR (and neither did I for that matter) so we may wait a little while for this one. I can tell you, though, that you can update Pitbull, kgpanels, Dominos, and FuBar and you'll get most of the stuff back working that you'll need for a functional raid UI.
And don't forget to check "load out of date addons" on the mod selection screen before you log in.
Enjoy the patch, and I'll update whenever I can.
