Ah interesting, thanks! I didn't see that meta-region mentioned on the Pricing page (http://aws.amazon.com/s3/pricing/). Is it priced the same as the two lower-cost U.S. regions (N. Virginia / Oregon) that it apparently overlays?
Oregon (us-west-2) is a separate region. I don't know if the US Standard "Pacific Northwest" location actually is in Oregon, but even if it is, it's classified separately.
us-east-1 is the S3 "US Standard" meta-region. For all other services, us-east-1 is just good old "US East (N. Virginia)". For S3, the two names refer to the same thing. It uses the us-east-1 pricing, no matter where your data is physically located, since it is us-east-1.