It’s still in alfa, but the SharePoint team announced a Visual Studio 2005 add-on for developing SharePoint solutions: “Visual Studio Extensions for SharePoint Services”. The features (I actually saw them working 
):
- Add sharepoint project type
- Item templates, site definitions (webparts, definitions, event handlers, features, workflow activities)
- Build, deploy, debug options
- WSS xsd for xml intellisense
- Utility for export content db’s
- Deploying for development: build and everyting is added and set in SharePoint (webpart in gallery, safe controls, etc)
Also this is something we’ve been looking for about 3 years? 
Way to go!