From what I understand, WCF is a platform and set of tools for building frameworks in .Net. Using WCF it's possible to create services that act like SOAP, or REST, but it's also possible to create other services of your own devising.
From what I'd read, it's possible for your WCF service to have a WSDL that provides a SOAP-like description of the operations it provides. Given that, you may be able to coerce Savon into making requests on your behalf.
However, I don't want to give you the impression that Savon was designed to make working with WCF from ruby easy. The truth is that Savon was created to make interacting with SOAP services easy. This means that any services that implements a traditional SOAP interface, with a client WSDL is likely to work, but anything slightly outside the box is more complicated and less unlikely to work without some tinkering.
Like most good software, Savon is open source, so I'd love to know how well it works for your WCF needs. If you find that Savon doesn't work quite for your use case, it might be good to explore either extending Savon directly to support WCF, or providing a separate gem for Savon-WCF that extends its functionality.
Feel free to open any issues on Github to explore or discuss this idea further. You might also find some discussions on the google group
Cheers,
-Tim Jarratt tjarratt@gmail.com https://github.com/tjarratt