One of the cool new features is something we call "ASP.NET Dynamic Data Support". In a nutshell this enables you to really quickly build data driven web-sites that work against a LINQ to SQL (and in the future LINQ to Entities) object model - and optionally allows you to-do this without having to build any pages manually.
The best way to see this in action is to watch David Ebbo's awesome 17 minute screen-cast:
For more info. : ScottGu's