I wonder if they have considered serving images through a separate domain/CDN and whether that would have had a bigger impact. Also, using CSS sprites might help.
"Premature optimization is the root of all evil". We used SimpleCDN for a while, but the increase in performance didn't justify the increase in complexity.
Oh, I agree. I was just wondering whether you thought about it and I guess you have. BTW Google Page Speed's biggest complaint for your home page was that images were not served from cookieless domains and downloading them was not paralellized.