C# 3.0 .NET Language Features

Implicit Typing
Generic Delegates
Lambda Expressions
Infered Types
Object Initialisation
Anonymous Types
Extension Methods

LINQ

.NET Language Integrated Query - (LINQ)
Standard Query Operators
Query Syntax
Deferred Query Evaluation
Conversion Operators

LINQ to ADO.NET

SQL Integration
DataContext
Entity Classes
Updates
Concurrency
Transactions

LINQ to XML

XElement
XAttribute
Querying XML
Creating XML
Adding to XML
Expression Trees