as you know i'm going through exactly the same thing atm!
It is very difficult to own the intellectual property of something when other people own urls/brands/companies with the same name.
Not impossible, but if your site
www.bananamail.co.uk is extremely sucessful the owner of
www.bananamail.com has a platform to make life difficult, my guy said to me "If you own the .com you don't have to worry too much about who has the .co.uk, but if you just own the .co.uk you should be wary of whoever has the .com" Also the .tv URL's are apparently very important ones for laying claim to the IP, although I have no idea why this is.
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