Just wanted to let folks know that a new update to the Autodiscover Whitepaper is now available. This now contains tons more information regarding certificates, web service URL's, best practices, etc.
You can find the whitepaper here:
You can find the Exchange team blog announcment here:
The only thing it doesn't really cover right now is load-balancing, for that you can see my series on CAS load-balancing here: http://blogs.msdn.com/brad_hughes/archive/2007/09/10/cas-load-balancing-certificates-autodiscover-and-webservices.aspx