Many of you would have read my earlier post on the What is what on Visual Studio 2005 SP1, ASP.NET AJAX RC1 and .NET Framework 3.0.
While the other two are more or less a future preview releases or a little new, let us talk about Visual Studio 2005 SP1 since Visual Studio 2005 is already in the market for quite some time.
Visual Studio 2005 SP1 covers a number of bugs such as slowness in the editor, default HTML Validator turning on and quite a few related to performance reported by folks like you.
The feature that has been added are support for ASP.NET AJAX, Web Application Projects & Web Deployment Projects which were earlier available as separate downloads / betas. If you had worked on Visual Studio .NET 2003, you would love the Web Application Projects and I am sure you would have searched for it when you first started using Visual Studio 2005.
So, I would highly recommend users of Windows XP SP2, Windows Server 2003 SP1 and Windows Vista users to download and use the Visual Studio 2005 SP1 to find improved performance and additional features.
The Visual Studio 2005 SP1 can be downloaded from here.
Omar Khan has a nice post on the Web Tools changes with Visual Studio 2005 SP1 here. A must read if you really want to know what is in it, to install.
Scott Guthrie has a nice post on the HTML Editing Performance improvements in Visual Studio 2005 SP1 here