SharePoint 2010 introduces rich new areas of functionality that create more choices and fresh opportunities for developers and solution architects. Sandboxed solutions, new options for data modelling and data access, and new client programming models with Silverlight and Ajax integration offer a step change in what you can accomplish with SharePoint applications. This guidance provides a deep technical insight into the key concepts and issues for SharePoint 2010 solution developers.
Online version: http://msdn.microsoft.com/en-us/library/ff770300.aspx
Downloadable version: http://www.microsoft.com/downloads/details.aspx?FamilyID=64b55569-2168-4545-8b7c-f185b2cf967d&displaylang=en