We are pleased to announce the availability of the beta of Visual Studio 2005 Service Pack 1.  

You can find a technical description of some of the fixes included in this service pack and download the beta by registering on the Microsoft Connect Site.  We’ll have the complete list of fixes posted when the service pack releases.  Pending feedback from you on this beta, our plan is to ship the final version in the next 3-4 months. 

VS2005 works well on Windows Vista.  Visual Studio 2005 SP1 will run on Vista but will likely have a few compatibility issues.  As you already know that Windows Vista will ship with the .NET Framework 3.0 pre-installed, We’re also testing to ensure that your .NET Framework 1.1 and 2.0 applications will work on Windows Vista so that your existing applications will continue to run as expected.  However, we will not support Visual Studio .NET 2002 or Visual Studio .NET 2003 as development environments on Windows Vista. You can continue to use Visual Studio .NET 2002 or 2003 on Windows XP to develop applications that can run on Windows Vista.  

you can get more information at http://blogs.msdn.com/somasegar/archive/2006/09/26/772250.aspx