In a high traffic application, like an online auction system, few ms could determine 'to win or 'to lose' the 'battle'.
I'm from Brazil. Here, I 'ping' local sites - like UOL - and receive replies in ~ 11ms. When I 'ping' US sites - like RackSpace - I receive replies in ~ 130 ms!
The point is: I need a (very good like RackSpace ) infra-structure to host my killer online auction application, but there's no (RackSpace like) options in Brazil... Assuming that all users are located here, in Brazil, is it 'sine qua non' condition to host my application here, in Brazil?
I think ~130 ms is a very high latency but, all users will receive this reply, sure?
Well, where should I host my application?
 Feel free to point me to any other very good host option other than RackSpace. I've cited it because I only know these guys...