Hot off the presses is a new resource for channel authors: the WCF Custom Channel Resources page at wcf.netfx3.com. This is a great portal for samples, documentation, and all things Channel-related.
The samples page contains updated versions of our PDC demos (WSE 3.0 TCP Interop and Chunking Channel) as well as new helpers for testing and generating config for your channels. Check it out!
UPDATE (06/21/06, 3:50P): updated links to point to our new community website