An update on a couple of small interface changes related to Ceilings. In 2010 with the ribbon we received more than one question about "What happened to the automatic ceiling placement?". The answer turned out to be nothing - just a trick of the eye. The confusion was understandable on analysis.
In 2009 you would enter the Ceiling command and start clicking away (more on that below). While in the command there was an unassuming contextual button in the option bar called "Sketch". This would allow you to enter a sketch mode rather than get the automatic flood behavior.
In 2010 this button moved to the ribbon and got a lot more attention..so much that many more people pressed it rather than stay in the "automatic mode".
Those who have taught Revit will know people often overlook the option bar despite all reminders - perhaps because it blends in with the toolbars. The fix was simple enough. The next 2010 update, and subsequenty 2011, indicated the current state next to the Sketch option as a toggle. There is actually no way to press "Automatic Ceiling" and the command is just the same "Ceiling" command yet it solved the issue by indicating the state.
oh yes....the other change is if you click more than once in the same place with the Ceiling tool in automatic mode you now get a warning. This was an issue going way back. We did have warnings for components but not items that were sketch based. No more piles of ceiling elements or floors for that matter.