I think the details of the release are best covered by others, such as Katrien’s summary of all of the announcements.

For my part the really interesting parts are:

• Release of ADO.NET Data Services (formerly Astoria). Mike Taulty has covered this tech fairly extensively which is worth a review.
• There are new features in WPF and performance improvements but in particular the release of .NET Framework Client Profile means that the barrier to deployment of WPF applications is lowered as the size of the redistributable is around 26.5MB which is more than an 85% reduction in the size of the 3.5 full redistributable.