Something changed recently and the Acid2 test renders incorrectly.
Acid 2 looks fine to me with r36130. Can you attach a screenshot of what's wrong? Also, make sure you don't have any Safari extensions installed - see <https://trac.webkit.org/wiki/FAQ> for details.
Created attachment 23235 [details] Screen shot of bug. Here is what I see.
Strange - I also cannot reproduce this.