Another new community author for the C# Developer Center
Charlie Calvert has added another new author to the C# Develper Center. Thomas Lebrun has added an article about extension methods. He gives a good solid overview of what extension metods are, how to use them, how to define them, and how to prevent collisions between different extension methods with the same signature.
If you aren't sure how you would use extension methods in your own work, it's well worth the read.