Back on January 4th, we reported Google Not Showing Localized Pages Within Country For .COM TLDs. We have specific examples showing that Google was not showing proper pages for .com domains, when one conducts a site command search, but restricts that search to a origin.
It appears based on Matt Cutts's Infrastructure status, January 2007 post that this should be resolved soon or even now.
I thought we’d nailed this issue in December, but we found another way that this can happen. I believe a fix has been submitted and is percolating its way through the system. Of the ~7 examples that I know of, I believe all but one is working now (and the remaining site is doing a chain of like five 302 redirects to weird/long/deep urls). However, if you 1) have a .com that is hosted outside the US, 2) searching on (say) google.co.uk for [site:yourdomain.com] returns your root page and all your pages for “Search the web”, 3) if you switch to (say) “pages from the UK”, the root page does not appear but the rest of your pages do, then this paragraph applies to you. I’d wait 4-5 days to let this second change percolate completely into our index, and if you still see the behavior after 4-5 days, please leave a comment with the name of your site.
So it has been 5 days since his post on this and we do see some improvements, but not all sites are yet a 100%, as far as I can tell.
SEOptimise tells his story, being a .com hosted in a UK data center.