What is C4MVC?  Well per the about us page it is:

Our Vision is to share knowledge and best practices around using the framework, as well as encourage community contributions that serve the greater good.

Through interactive sessions, projects, and aggregated blog feeds we hope to provide:

• A way for new developers to use the framework the right way.
• Techniques and tools to allow experienced developers to develop with less friction.
• A self supporting community.

Per my definition:

A virtual user group on Wednesday mornings where I can listen in on the Asp.Net MVC big guns discuss the topic of the framework that I need to learn better.

Besides the great free content such as last weeks Advanced MVC2 topic sometimes, just sometimes, you can win some stuff.  In my case, I loves me some 30 day subscription to TekPub which also happens to have a lengthy Asp.NET MVC series. Now the only problem I have is finding the correct window to pull the pin this content grenade so that I can put together 30 days of face melting guitar solo mind melding content assimilation.  Parent of 3 (4 and under) makes that a GTD challenge.

The C4MVC.NET (google) group is open to anyone to join so come and join the group to get some good nuggets of Asp.net MVC knowledge on!  No really, join now!