Currently Being ModeratedOct 26, 2013 9:38 AM (in response to Ryeezi)
I've found that tapping / touching (NOT holding down for 2 seconds!) the power button on my Macbook Air gets me past this screen. Can't remember exactly what happens. I think the screen goes dark and then either I land on the desktop or the login screen, or I have to touch a key to wake the computer up first and then get to desktop or login screen.
Things seem to be working on my iMac. But on my Macbook Air, Mavericks has really messed up something with iCloud.
For the record: I don't use Apple Mail, nor am I using iCloud Keychain.
I've also had problems with the iCloud System Prefs control panel. Oddly it seems to have fixed itself just a few minutes ago, but I'm quite confident the problem will come back. The problem was: I'd open System Prefs > iCloud but the apps in the list would all be grayed out. I would enter my password and it would not be rejected — but the apps still wouldn't become visible.
In my opinion, iCloud is a mess. I'm just about to pull EVERYTHING out of iCloud (if I can figure out how) and just use Dropbox, which works so so much better.