This is one of the biggest failings of SimpleDB that I think keeps it held back from being a huge success, the region dependency of it and the seeming lack of support from Amazon (the only product whose forums frequently go a week without a reply).
Had SimpleDB has an optional global redundancy for quick read/writes in all locations, I think it would have been the killer product a lot of people were looking for.
Instead I have to roll my own with a fully connected CouchDB graph of servers. Ahh well.
