Aside from the Silverlight announcements which seem to have stolen the show so far at Mix07.
A couple of other interesting pieces to watch, codename: Astoria:
The goal of Microsoft Codename Astoria is to enable applications to expose data as a data service that can be consumed by web clients within a corporate network and across the internet. The data service is reachable over HTTP, and URIs are used to identify the various pieces of information available through the service. Interactions with the data service happens in terms of HTTP verbs such as GET, POST, PUT and DELETE, and the data exchanged in those interactions is represented in simple formats such as XML and JSON.
And codename: Jasper:
Project Jasper is geared towards iterative and agile development. You can start interacting with the data in your database without having to create mapping files or define classes. You can build user interfaces by naming controls according to your model without worrying about binding code. Project Jasper is also extensible, allowing you to provide your own business logic and class model. Since Project Jasper is built on top of the ADO.NET Entity Framework, it supports rich queries and complex mapping.
I'm finding the what's being released when and with what ship vehile is getting confusing/complicated, with .NET 3.5, C# 3.0, Visual Studio Orca beta 1, ADO.NET EF, Linq, etc. and I'm not the only one.