GoogleBot didn't spider my new site?

In late December 04, I launched a new website and by early January I had added my URL to Google. Within a couple of weeks, Google had listed me - but just my domain name (so when I search for 'domaindotcodotuk' I just get a 'domaindotcodotuk' link).

So last week I added a simple HTML Link from my 2 year old website (PR5) to my index.html page. I have checked today, and my old website was spidered (including the link) but my new website hasn't. When I search in google, I just get a link for the domain name.

Can someone please explain why this is? Is it something to do with this 'Sandbox' theory were I have to wait 6 months to be spidered or could it be the server host I'm with (it's a different company to my old website)? Please help...