I am compiling a list of the options that USPS uses on their shipping tracking numbers. I remember a few years ago that the U.S. Postal Service would only show that the package was either delivered or shipped. Now they show a little bit more timely updates, such as when it reaches the destination cities' sort facility and leaves the origination cities' sort facility, as you can see below. I hope that "Processed through Sort Facility" this means it arrives today.
Processed through Sort Facility, Mar-28-10, 03:26 AM, [Destination Facility]
Processed through Sort Facility, [Origin City]
Electronic Shipping Info Received, [Origin City]
Package was tracked with the uber cool boxoh.net package tracker + notify.me (which sends me a text when the status is changed)