I posted this over in Link Development a few days ago and got no answer. MB's mailbox is full so couldn't get him to move it.
Here's my problem -- I've an older site with ~40 backlinks on Google. Just opened a new site (2 weeks ago), same IP, using virtual hosting (Linux/Apache2). Each site comes up when the domain is entered in a browser-in other words www.site1.com vs www.site2.com. Each when pinged returns the quad IP address. But link:www.site2.com returns www.site1.com's backlinks! Is there a simple explaination of where I've screwed up?
Maybe you haven't screwed up at all. But the engine has associated site1 with that IP address, thinking it was a non-shared IP. And now you've shared it.
I think the test would be to see if G is aware of *anything* related to site2 yet; Has Google spidered the site and are there any fully-formed (Title plus Description or snippet) page listings for site2 yet?
If not, it may just take them some time to move your domain from their "simple non-shared IP site" list to their "shared IP site" list. I'm speculating that these lists exist in some form, because there are probably many more filtering and canonical-URL-resolution processes that have to happen for shared IPs.
In the meantime, check your server headers [webmasterworld.com] and make sure that no redirect responses are used to 'get to' each of your domains. If they are, then you'll need to clean that up.