1. Client SharePoint Object Model. Applications that do not run inside SharePoint as a WebPart can now make use of a new library to access SharePoint information. This library takes away most of the complexities around invoking the SharePoint web services. Very useful in e.g. Silverlight applications.
2. New deployment package. SharePoint 2010 introduces/improves greatly the WebPart packaging and deployment using the new Windows SharePoint Package. It is now much easier to publish a feature or WebPart to a site or farm.
3. Sandboxed WebParts. Web parts can be added to a site in a sandbox. A sandbox means that the WebPart will run in its own server-process. Furthermore, it has restrictions imposed on it (such as the time it may run). This greatly improves the stability of the environment as faulty WebParts no longer crash the SharePoint process. Especially interesting to know is that using the sandbox you don’t need administrative privileges on a farm to deploy a WebPart to a site.
4. Improved Visual Studio 2010 support for SharePoint. In Visual Studio you can now:
   1. Use SharePoint templates to get you up-to-speed
   2. Design WebParts visually as if they are ASP.NET controls (which in fact they are…) (see this article for some extra info)
   3. Browse through a SharePoint site using the SharePoint Explorer Window
   4. Deploy WebParts to SharePoint through new wizards and the new feature/webpart package
   5. Hit F5 to automatically build, deploy, reset IIS, attach the debugger and open the page with the WebPart…
5. Linq2SharePoint provides a LINQ query interface to search through list and site content. Regrettably this feature is not available in the new client object model (to be used by apps not running inside SharePoint)
6. The Developer Dashboard provides statistics on page load time, executed queries, query execution times, server info, etc. Very useful! See this post for a preview…
7. Silverlight is now supported out of the box.
8. Business Connectivity Services is the follow-up of the Business Data Catalog. It is now much more powerful and even easier to use. You can relatively simple create an ‘external list’ that behaves just as any SharePoint list, but of which the content is hosted in another system (SQL Server, SAP, …) It even supports write operations to the lists! Visual Studio comes with templates for creating new BCS adapters for unsupported content sources…
9. SharePoint Designer has gone through a major redesign making it much more useful.
10. New WebService interface allowing for easier and more extensive access to SharePoint functionality. Moreover, REST support has been added to query lists and content. A very cool demo I saw was the combination of the REST interface with the improved Excel Services: A graph in an Excel file in a SharePoint library could be accessed through a (REST) URL and posted as a (PNG) picture on a webpage or inside PowerPoint. When the data in the excel file was updated, the graph was adjusted in PowerPoint and on the webpage. The Url looked like: http://mysharepointsite.com/lists/documents/excelfile.xlsx/mygraph, where mygraph was a named set in the Excel file (named sets are a new feature of Excel 2010). Very cool.

Combine this with the new features (SilverLight, Performance Point Services, improved Excel Services, etc.) and you’ll find that SharePoint 2010 is worthwhile upgrading. What I couldn’t test at the TechEd is the stability and performance. Hopefully that has improved as well…

1. Writable Bitmaps: These allow you to create bitmaps from inside the SilverLight applications. This functionality forms the basis for many new SilverLight effects. A cool feature of the writeable bitmap classes is that you render a portion of your XAML into the bitmap and act upon that rendering. Here at TechEd I’ve seen some cool demos like magnifying glasses, or video frame capturing that use this.
2. Communication framework: SilverLight applications can now communicate with each other. This allows you to modularize your pages. For example, I can think of a set of SilverLight based SharePoint WebParts that communicate about the range of data that they are showing.
3. Offline capabilities. SilverLight becomes true RIA… You can now take SilverLight applications offline. This allows you to start a SilverLight application from your start-menu or desktop. You do not even have to be online to work with the SilverLight apps.

This is just a top 3. There are much more features and improvements like improved development support in Visual Studio 10 and Microsoft Blend, improved integration into SharePoint, improved data binding, RIA services for data access, etc… SilverLight is developing fast!

Apparently I’m not the only one who loves LINQ. You may already know about Linq2Sql, Linq2Objects and Linq2Entities. However, did you know that there is now also …

• Linq2RiaServices, allowing simple access to data in the middle tier from SilverLight applications
• Linq2ADODataServices, providing similar functionality as the Linq2RiaService, but utilizing the ADO.NET Data Services framework.
• Linq2SharePoint, allowing you to query SharePoint lists and sites from within a SharePoint WebPart, and
• Linq2Azure, which is used to query Azure storage.

 Seems that every locally or remotely stored set of object  gets a Linq interface…