This question is more of a probe to discover what people are doing in the community, in practical situations, than a specifically targeted question. I have searched pretty broadly about this, and while I have found a lot of bloggers advocating contract-first service design and some comments backing them up, I have yet to find much practical information about implementing contract-first with WCF, the pros and cons of doing so in a real-world environment, etc. I have recently done some extensive research into SOA, primarily through Thomas Erl's books, and one of the primary concepts he advocates is contract-first design.
My questions are as follows:
One of the major problems with contract-first development seems to be tooling. Svcutil is the only thing I have found that can generate service code from a contract, and it has some pretty poor output. Its single-file, chock full of attributes and code-generation artifacts, and it basically needs to be regenerated and replaced any time the contract is updated. I would prefer a better approach, preferably something that doesn't require regen-replace. I'm fine with manually creating the service-side contract even, assuming it is practical in a real-world scenario.
EDIT:
While WCSF solved my immediate needs, learning about Protocol Buffers and Service Factory are both intriguing tools that I am sure will help me in the future.
WSCF provides a contract-first tool with VS integration. Checkitout. (free)
As of July 6th, there's a binary release with a setup program.