I'm having to post this in Firefox because Gamestyle doesn't seem to like Opera any more. The board loads nice and fast in Fox but deathly slow in Opera. After I've loaded it in Opera the whole thing slows right down - all other pages load really slowly, and even the options menus come up slowly. Opera runs just fine until I go to GS on it, then I have to close it and re-open it to get it back to normal.
It started after I went to that Rotten Tomatoes link in Sprite's post, but through trial and error I've discovered that it is GS and not RT that causes the slowdown.
I've tried all the obvious stuff - clearing cookies and cache, and running Spybot and Adaware, and rebooting my machine.