I would like to suggest that you seperate servers for europeans and americans. For the whole day for me (as a european) the server was performing great. Now, that the Americans log on the server turns to ****....
Regionalised servers is one of the worst thing introduced over the past few years. All they need to do is upgrade what they have.
This is truth. You don't want to be on the losing side of the population wars. City of Heroes is one poignant example of that. The Europlayers split off to the EU servers in 2005 after playing with the US crew for a year, but 2 years later, it's dead on all but the British servers. Segregating US vs International doesn't make sense when you have a basically "shardless" setup like you have here currently.
This is the better structure to go, believe me. Whether or not they do it WELL is another thing; that's where beefing up the existing servers to handle all traffic points matter.