The SDK (Software Development Kit) for SharePoint 2010 RTM’d slightly after the product itself and is now available.  This download contains both SharePoint 2010 and SharePoint Foundation 2010 SDKs, which you may install separately.  About 450 MB required to install both of them, but the download is much smaller.

Download the SDK now.

Tons of new “How-To” topics and code samples!

• Code samples for SharePoint Foundation
  • Implementation of IBackupRestore
• Code samples for Business Connectivity Services
  • AdventureWorks .NET Assembly
  • AdventureWorks ASP.NET Web Service
  • AdventureWorks WCF Service
  • AdventureWorks 2008 .Net Assembly and Web Services
  • AdventureWorks 2008 Declarative Outlook Solution Reusable Components
  • AdventureWorks 2008 Declarative Outlook Solution Sample
  • Authenticating and Consuming Data from NetFlix (Web 2.0 Application)
  • BDC Model for XML Snippets
  • Custom Web Part and Word Add-in Sample
  • Sample Orders .Net Assembly and Web Services
  • Sandboxed BCS Workflow Sample
• Code samples for Enterprise Content Management
  • Content Type-Based Metadata
  • Creating a Routing Rule
  • Custom Document ID Provider
  • Managed Metadata Dependencies
  • Pausable Custom Timer Jobs
  • Publishing Cache Services
  • Silverlight Controls and Silverlight Thumbnail Extraction Sample
  • Retention Events
• Code samples for User Profiles and Social Data
  • Combine information from my public profile on Linkedin (or Facebook) with my User Profile
  • Gold star or thumbs to a colleague
  • Insert an event/document change event in feed
  • Share a link with my colleagues
  • Social data statistics
• Code samples for Visio Services
  • Annotations Sample
  • Custom Error Messages Sample
  • Mouse Interaction Sample