1. New User Interface including Ribbon
2. Sandboxed Solutions
Also called as User Solutions, is a new concept which allows site collection administrators to deploy solutions at the site collection level which is safe to run and not affect the other site collections and web applications running on the same farm. Farm administrators can monitor sandboxed solutions and place restrictions on the resources, such as memory and CPU cycles, they can use. Sandboxed Solutions does not cover full SharePoint object model but it addresses the key scenarios like custom web parts and event receivers. The solution deployment as in SharePoint 2007 is still exists in SharePoint 2010 but those solutions are called as Farm solutions.
3. SharePoint Workspace
Microsoft Office Groove has been renamed to SharePoint Workspace in SharePoint 2010. SharePoint Workspace provides local and offline read-write access to SharePoint lists and libraries and also incorporates offline-online synchronizations.
4. Stsadm command-line tool is superseded by Windows PowerShell 2.0
5. BCS(Business Connectivity Services)
Provides Read-Write capable connectivity from Client and Server to Database, WCF/Web Services and .Net Sources.
6. Client Object Model
The SharePoint 2010 Client Object Model is a very cool feature of SharePoint 2010 Foundation Server that enables developers to write applications that access SharePoint data from a .NET application running on a client computer, from a Silverlight application, and from JavaScript running client-side in a SharePoint web part. The client object model enables this without requiring the developer to write or install code on the SharePoint server. (Using Microsoft.SharePoint.Client namespace)
7. Visual Web parts
8. Redesigned Central Administration web site
9. Shared Service Provider (SSP) no more exists
SSP's have been replaced by Service Applications in SharePoint 2010. Earlier in SharePoint 2007, all services were combined into a SSP. Now in SharePoint 2010, all services are running as independent Service Application.
10. Built-in Silverlight Support
11. Rich and Improved Theming Support
The new 2010 themes use an entirely different design. SharePoint 2007 themes used CSS and images while the new 2010 themes use the .thmx format. This means themes can be easily created using PowerPoint or any other tools(ex Microsoft Theme Builder)
12. Multiple Browser Support - IE, Firefox & Safari
13. Rich Media support and Digital Asset Management
SharePoint 2010 includes a Media web part built using Silverlight, Video content type, Audio content type, and Image content type.