I just pushed Kayak 0.7.0 up to NuGet. Here’s what changed:

• Support for 100-continue. This will speed up most PUT and POST requests quite a bit since clients won’t wait for the 100 Continue status (usually about 200ms) before sending the body anyway.
• IHttpRequestDelegate implementations will get null for the request body producer if the request headers do not contain Content-Length or Transfer-Encoding: chunked.
• Implementations of IScheduler, IServer, and ISocket are now private and cannot be directly instantiated using the new operator. Use KayakScheduler.Factory, KayakServer.Factory, and KayakSocket.Factory instead.
• Fixed a typo bug in socket implementation so that if BeginReceive synchronously throws an exception the error-on-read logic is invoked (previously error-on-write logic was invoked).
• Several small optimizations to socket implementation.
• Improved test coverage of HTTP transaction logic.

As always, play around, stress it, and report your experiences to the Kayak Google Group.