The goal of this library is to provide simple and straight forward interfaces to the various shipping web services: FedEx, UPS, USPS, etc. (Only FedEx is supported at this time)
This is not a shipping abstraction layer, meaning there will be differences in how the classes are used. In my opinion, this is the best way to approach this because there are too many differences between the services. Trying to create an abstraction layer significantly limits the feature set that each carrier offers. Instead, this is a collection of libraries where each classes' core focus is to give you simple and complete access to the web service at hand.
More documentation and examples will come in the next week or so. I want to mature the library a little more.