It could just be me, but one thing that's happened since the new design has been launched is that, more than once I've typed out an answer to a question, and then once I've read through it to double-check there's no glaring errors, I go to post the answer, but stop because the button is disabled. I then go through a bit of a rigmarole of searching round the page to see if I've missed ticking any boxes, adding any tags, etc, then copying all the text to clipboard/notepad and then reloading the page to make sure the question hasn't been deleted/closed/migrated, then finally try clicking the button to see what the error message will be - only for everything to post correctly with no problem.
I think this is because, to me at least, the "Post Your Answer"/"Post Your Question" buttons look exactly like disabled "greyed-out" buttons in Windows (and in many web apps), to the extent that I seem to be mentally conditioned to not even consider clicking them until I've looked all round the form to see what I've missed.
As an example from a popular web app many of us will be familiar with, here an enabled and disabled button in Gmail, notice which one the Post button on here looks like:
Is there a way that the various post buttons can be made to look a bit more "active" perhaps a bit of colour, or something along those lines?
(Firefox 4 on Win7 & Vista, in case it matters)