No, not the only thing, but it's the main thing that will make the biggest single difference, primarily because of geolocation delivery tools.
Other things you can do is to obtain as many UK-based and UK-relevant inbound links from UK directories/journals, industry-specialists, etc. Remember, it will not have the same effect/impact as the geolocation filtering of a UK server.
I'm interested to read this as I'm having a similar problem. In my case I have a .co.uk domain, no .com domain, and my server is based in the U.K. I have links from predominently .co.uk websites, all my prices are in pounds...My products are musical instruments so no reason the americans would be more interested, My geo-location thing is set to UK in google.
But still have a massively greater number of US visitors compared to U.K. Is there anything else you can think of to improve the amount of U.K visitors?
I should say my rankings for keywords are similar in google, and google UK searches.
Thanks
Tom
This is despite the fact I am in the UK along with my website. I don't know why this is happening but thought I should point it out.
That's a weird one, and totally unhelpful.
Time to get a new stats package, methinks.
ADDED
Can you see the BBC video content for the Beijing Games? If you can, the BBC system detects you as UK. If you can't then you might want to have a word with your ISP about your own IP.
All this will give a distorted impression of the number of US located visitor numbers.