As others have said most flash sites of this kind did the exact same hack and provided an HTML fallback that used JS to replace the fallback div with the correct Object/embed for the browser.
Back in the days , making a flash site meant making an accessible fallback as well, and i always designed a pure html fallback for each full flash website i made ,Heavy javascript sites are not accessible by magic.
The irony is this site would have been smoother using flash. On my mack , this webiste is pretty slow and hard to use.