Visual Studio 2010 includes new project templates for creating solutions that target Microsoft Office 2010

You can create solutions for 32-bit and 64-bit versions of Microsoft Office 2010

The code that you write in Office projects is the always same when you target the .NET Framework 3.5 or the .NET Framework 4

You can combine multiple document-level and application-level office solutions and deploy them as a single package

When you target the .NET Framework 4, it is now possible to deploy office solutions without the Office primary interop assemblies