ReST stands for Representational State Transfer (Like the one used in Twitter) and defines an architecture to create network applications, typically over the World Wide Web. In most cases, the protocol used for a ReST client-server communication is HTTP.
ReST is not SOAP and hence if we want to use ReST with BizTalk Server, the adapter to be used should be able to exchange non-Soap messages. So its a bit limited.
Nitin Mehrotra (MSFT) and Team has published a wonderful article with a great detail. I believe this would be the only help available in the topic.
CLICK HERE to go to the original article.