I can understand wanting a change, and I agree it would be a good idea, but just to say that it might kill the series if it was in another American city is a little ridiculous. 

Also alot of people are forgetting,  Vice City was not only a location change but it was also a time period change.   Maybe they could do a 70s London or something

I shouldn't have used the would "Kill" i should have said damages because it could be regarded as to attached to US and that would really limit the oppotunity for potential future GTA games.

I say Istanbul

I think any of these could be good: Hong Kong, Tokyo, London, Sao Paulo, Rio de Janeiro, Havana, Chicago, Moscow, or Mexico City.

I don't see why a change would go against the series good. It's a good way to increase interest from other regions, a GTA at Europe would make sales in that region be even better without affecting NA sales. I understand there is something like a anti-japanese game movement right now, at my school people pratically disconsider japanese games, even FF is forgot by teens nowadays, they prefer Halo.

Moscow

They really need to stop making GTA games, i doubt they will, but it feels like they're just milking it. GTA4 was really bad. GTA peaked with Vice City.

Birmingham :)

Newcastle :P

Tokyo, Singapore or Shanghai. I think giving the series and asian twist would be so so awesome, and enough to get me back into it!