If you are a C# developer who doesn't use LINQ feature, then you should.

Java doesn't support LINQ type of query syntax against collections.

If you are an old timer C# developer who hasn't really started using LINQ (hard to imagine anyone not using it by now), then you are missing out a big productivity boost.

Programming in Java everyday makes me realize how useful it is.

The same thing can be said about these C# feature:

• using syntax to create alias of a class name to in case of namespace crash (e.g. two classes named the same and used in the same context)
• Event (I mean EventHandler<T> and += stuff)
• Lambda expression (=> stuff that allows you to create piece of implementation in line)
• Anonymous class (a way to create a structure on the fly) - super useful for passing a simple data structure without creating class (prevents class explosion)

These are C# feature I miss the most.