One of my pet peeves is when people are so "in" the webkit world they don't bother to even list the unprefixed version. I too looked at it in Firefox, and things actually look a bit broken. My guess is adding the unprefixed version would probably fix the majority of the errors I see.

I won't go so far as to say stop using prefixes, but ALWAYS include the unprefixed version last in the CSS stack. It's so easy with Sass also.