Businesses that aren't growing anymore usually get valued based on earnings. The P/E of the S&P 500 is about 20 (perhaps a little less after the recent market turbulence), which means that HotOrNot's price would be about half the average publicly-traded corporation, including all the old-line manufacturing businesses and companies in decline.
P/E ignores a lot of things, too. Old-line manufacturing businesses usually have a ton of assets (machinery, land, etc) that boost their valuations.
I doubt HotOrNot has much more than the brand name and domain, as far as assets are concerned.