The superficial reason is that there are multiple flash streams page, each appearing to be of quite a high bit rate, as well as lots of data-driven content. The underlying reason of how this causes a crash, not just a slow down, I don't know.

In my case, the page opened slowly but ran for a while. I switched to here (Ctrl + bksp) to report and it all went haywire. I also had FAM open.

Interesting but don't think it's a real sign of websites to come, other than by confused web designers who throw everything on one page!