I tried Orcas (new version of visual studio) over the weekend. I really like the new interface. Though the interface is not drastically different, but its sleek look on Vista is awesome. Feature wise, there are quite a few, but one feature which i liked a lot is the ability to multi target. As i heard from scott guthrie, Orcas is the first version of Visual Studio that enables developers to target multiple versions of the .NET Framework. This means that you can open or create a project that explicitly targets either the .NET Framework 2.0, 3.0 and 3.5 releases, and Visual Studio will automatically filter intellisense, toolbox controls, and add reference dialog items (among other things) to only show those features supported within that specific version of the framework.
Then there are good C# features such as automatic property generation. So from now we do not need to write both private memebers and thier public properties. The compiler can automatically generate this for you!!!!!
Another feature which i ahvent tried much but read about is the object and collection initializers. Though i felt that isn't an Object Initializer already present in the language in the form of a constructor? I dont know yet, will have to dig deep to find out whats going on inside.