Alex blogged the web.config entries for enabling Velocity CTP3 in web.config for ASP.NET Session State.
Since I'm doing my talk on Velocity this week I took the time to update my Quick Reference Sheet for PowerShell commands.
Download it here.
Essentially the only change that I could tell is the -Notifications flag was added. You use this parameter to enable the cache notifications feature when creating a new cache, or updating an existing cache.
For a more complete difference between CTP2 and CTP3, read this blog post.