Samizdata - 1:04 pm on Oct 3, 2010 (gmt 0)
perhaps because they have no inbounds to their website and this is the only way that google can find it?
Googlebot does not require inbound links to find a registered domain.
Various bots will start sniffing around as soon as the DNS resolves.
The Add URL form is generally irrelevant but doubtless still has some uses.