ScottGu has some great posts on C# 3:
- The C# ?? null coalescing operator (and using it with LINQ)
- LINQ to SQL: Part 8 (this is an 8 part series, check the top of the post for links to the first 7)
- Automatic Properties, Object Initializers, and Collection Initializers
- Extension Methods
- Lambda Expressions
- Query Syntax
- Anonymous Types
Some more useful links:
- MSDN: Overview of C# 3.0
- David Hayden: C# 3.0 Tutorials and Examples
