I have been re decorating my room so have had my imac boxed up for about a week. before this time it was screaming even though it is only 2007 base 2ghz. I put this down to the recent upgrade to snow. I just plugged it back in now to watch some youtube videos and the whole thing is chugging through youtube as choppy as anything. It's also putting huge huge load on the processor and cases safari to quit. Just thought it was worth mentioning as it is similar to what others are experiencing with the new imacs.