If you had a current domain xyz.com but you also wanted to buy xyz.co.uk but you also wanted the same content for both? The reason you would be doing this is if you wanted your site to turn up on search results if the UK users searched for UK ONLY. What is the best way to handle this? to avoid duplicate content and to be listed on the search engines? A registrar forward? some other technique?
.com and .co.uk don't affect the rankings very much at all. When you search for "UK results only" you are requesting sites hosted in the UK rather than .co.uk domains. My advice would be to stick with the .com and to host in the UK (if thats your target market) and then use forwarding to forward the .co.uk to the .com If you want to host the .com in the US to target that market and then host the .co.uk in the UK then this will work as long as you don't have exactly the same content. It means maintaining 2 different sites with 2 hosts though.
So basically, If I want to target UK customers, especially when they click the "uk results only" I should look for hosting in UK. Thanks mad4.