Ok, maybe that is a bit of an over-statement, but one of the things that really struck me during PDC 2008 was that the word SOAP was hardly mentioned, and when it was, it was in passing with a “ohh, yeah, SOAP too”.  It was mostly interesting because of how dramatically different it was than just a few years ago when SOAP was being dropped every other word.  This is a bit of a “well DUH” statement for many in the industry, but it was interesting to see it finally manifest itself “officially” at PDC.

This is not to say that SOAP  is going away. Microsoft is continuing to support SOAP.  The key takeaway is that SOAP is no longer the “use it every where all the time” type of technology that is was being positioned as not too long ago.  REST seems to be winning or has won the battle as the best way to send data across the wire.  It’s simple, easy to understand, and can be consumed or emitted by even the simplest of development environments.

SOAP still has its place in certain interop scenarios and other “-ability” type of situations.  But by and large, if you are tying systems together, I think it is best to start with REST and then see if you need to move to SOAP, and not the other way around.  With hard-wired network connectivity being very, very reliable and with stateless programming models dominating, a lot of the higher value services we used to need to compensate for poor networks or environments have decreased.

On that note, make sure you check out the WCF REST Starter Kit.  The Kit will help you get started building REST applications with guidance, templates and sampmles.  Check it out.