I know this is a super old thread, but I just found out about the UPS RESTful API happening, because they told us last month that we needed to switch. Why they didn't tell us 2 YEARS ago, I don't know.

Anyway, @Jason Baginski, do you still have any information about the XML to JSON mapping you did? I'm going to need to do that as well. I managed to move us to the Stepping Stone URLs to keep using the web services with OAuth token, but now I need to go full RESTful. I have no issues talking to the REST APIs, getting the token and all that, but the JSON that comes back is WAY different than the SOAP XML and I need to map the JSON elements into my own class objects because we wrapped/abstracted the UPS API calls into our own central web service so our internal apps have a central point for talking to UPS through a local interface. The point is, I can't find half the data that used to be in easy to find XML elements. EstimatedDeliveryDate in the TrackResponse, for example. Where did that go?