The USPS has announced rate changes which will go into effect on April 17th. Full new rate tables can be found here:
Not sure why it isn't on that page, but the post offife will be introducing Priority Mail: Flat Rate Regional shipping boxes. Have yet to see the regional map, but allegedly if using one of these boxes to mail within to an address within the same region you get a substantially discounted mailing price. Guess will have to wait and see.