Created attachment 70092 [details]
Example of hover flickering
You can check it out by interacting the side links of the portfolio section of http://jellylabs.com/portfolio/. When you click on them, the text rendering on the whole page flickers for a second and then goes back to normal. You can see the same effect on the video attached just by hovering the links. This bug is present since over a year ago at least in Safari and all the nightlies, so I guess it's a duplicated one, but couldn't find a match.
I think this is a quite serious rendering bug, and maybe it's me… but I find it even more obvious since Safari 5.0.2.
You can see a live demo of the bug on http://jellylabs.com/ (the home page) as well. Just hover the flickr pics.
I cannot reproduce this, but this certainly looks like an area we could have a bug in. Are you seeing this on multiple machines?
*** This bug has been marked as a duplicate of bug 23364 ***