It's actually a really good example of very poor content delivery.
As was mentioned earlier, this could have easily been accomplished in Macromedia Flash.
Cobbling all of this together in JavaScript has probably more to do with either programatical self-masturbation and ego-building, or the fact that they couldn't do it any other way, their argument being: 'I don't do Flash'. There certainly wasn't any real attention being paid to the needs of the end user.
If any attention had been paid to the end user, the author of this site wouldn't have done what he / did here...