Didn't they spend 2 billion buying the 111 Eighth Avenue office in Manhatten at the end of 2010? I believe that is data center realestate.
It could be for transatlantic latency, but this would just be between the US and European data centers anyways.
In short, no, I don't think latency would be a big deal here. Correct me if I'm wrong.
Latency matters that much.