Granted, it's for a rather obscure term (the name of my dominant website), but I'm still hella amused. Google also keeps hitting it over and over to check for updates at an obscene pace, like it likes what I'm putting up there or something. I will have to investigate this further.
It happends to me twice and i detect how google does it: When you register the domain, the registrant (godaddy, misk, etc) shows somewhere the "new domains" and Google find it there. So, its not exactly truth that your site do not have any incoming link.
Well, I have another site that's been a lot harder to get Google's attention with. I suspect it may be because of the matching rDNS. Either that or actually having quality outbound links is something Google appreciates.
Google will try and match obscure terms with pages on your website. I have a few sites that initially get indexed without any inbound links and will show up in the SERPS for various non-competitive terms.
I wouldnt expect it to last long, but if its not a very competative keyword you should be alright for the mean time
Its no big deal to get top-10 position with some obscure keyword phrase you would get ranked with anyways, but no one is searching using that phrase.