Marc blogged about this last week (here), but I wanted to add a little more detail to what he said and why it's a "big deal" for you, if you are migrating ASP.NET Web Applications.
Among other things this add-in has templates that will make migrating web applications from Visual Studio 2003 to Visual Studio 2005 easier. The "big deal" here is that it maps the architectural model for web applications from VS 2003 to VS 2005, so that during the "upgrade" process you won't run into as many issues.
Just an FYI, this is not available (i.e., won't run) in the free version of Visual Studio 2005, otherwise known as Visual Web Developer 2005 Express edition.
Here's the link to the download, but pay particular attention to the installation statement at the bottom. You have to install the "Update to Support Web Application Projects" first and then this add-in.
If you didn't get the link from Marc's post, here it is again
~ Robert Shelton
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