View Thread, Original Norman is quite right - if you save the picture to your hard drive and then open it up in PHotoshop and enlarge it to 600 pixels, it is quite fuzzy.
Several factors are probably at work here.
A fast server on a fast backbone helps, but I believe the real reason is that the graphics, while quiet attractive and informative, have been kept small. If these photos were increased in size you could find them easily, but the busy nature of the graphics makes them hard to see. I just visited a site that has photos that load incredibly fast. Incoming mail is certified Virus Free.