I just came across this post at Steve Maine’s blog. I thought its worth sharing with you all: 

Conceptual Overviews:

• Web Programming Model
• AJAX and JSON
• WCF Syndication (Atom and RSS)
• Partial Trust

Class Library Reference (not exhaustive):

• System.ServiceModel.Web Namespace
• System.ServiceModel.Syndication Namespace
• System.Runtime.Serialization.Json Namespace
• SyndicationFeed Class
• SyndicationItem Class
• WebOperationContext Class
• WebServiceHost Class
• WebGetAttribute Class
• WebInvokeAttribute Class
• WebHttpBehavior Class
• WebScriptEnablingBehavior Class
• DataContractJsonSerializer Class

Configuration Schema:

• enableWebScript
• webHttp 
• webHttpBinding 

Samples:

• Web Programming Model

  • Basic Web Programming Model
  • Advanced Web Programming
  • UriTemplate
  • UriTemplate Table
  • UriTemplate Table Dispatcher
  • WebContentTypeMapper
  • HTML Form Handler
  • Push-Style Streaming

• AJAX and JSON

  • Basic AJAX Service
  • AJAX Service Without Configuration
  • AJAX Service Using Complex Types
  • AJAX Service with JSON and XML
  • JSON Serialization
  • Weakly-typed JSON Serialization (AJAX)

• Syndication

  • Intro to Syndication
  • Loosely-Typed Extensions
  • Strongly Typed Extensions
  • Streaming Feeds
  • Feed Formatter (JSON)

• Partial Trust

  • Partial Trust client and server

• Everything and (a picture of) the Kitchen Sink (Thanks, Justin!)

  • http://samples.netfx3.com/PictureServices/