[webkit-dev] 10.4.7 WebKit seems more 'flickery'

I don't have any hard evidence, (or a 10.4.6 system to go back to) but I have seen several instances since upgrading to 10.4.7 where web pages in Safari do a lot of unusual flashing/flickering that I have never noticed before. This might be a red-herring, but on <http://www.apple.com/ilife/ quicktour/iphoto/>, if I drag the scroll thumb around the 'Play All' section in the middle flickers with each scroll movement. I have seen similar things when just loading pages as well. Does this ring any bells with some change that went into this version of WebKit? FYI - Dual 867 G4 MDD