Three sample chapters on Infrastructure and Security Considerations, Basic IM and Presence Scenario and Remote Call Control Scenario has been published to the web.
I saw it yesterday but wanted to read it before I published the information (so I could say something slightly intelligent about it ;-)
The sample content is exactly what I want to see in a resource kit. There are some very detailed explanations on what happens behind the scenes. For example a good section in "Basic IM and Presence Scenario" covers "Examining the Technical Details Behind the Login Process" and has very detailed explanations on e.g. the entire auto-disovery and authentication process and spiced up with SIP snippets.
Of course it's written by some bright Microsoft guys namely mr. Dialplan (Joechen Kunert), Jeremy Buch and Rui Maximo.
Find the book on MS Press here (Can't wait to get my hands on the book and Microsoft if you need a reviewer ... then I'm right here ;-)