Efectivamente. http://msdn2.microsoft.com/en-us/vstudio/aa948854.aspx Q: Why support Visual Basic 6 and not Visual Studio.NET 2003 on Windows Vista?
A: Visual Basic 6.0 is still being supported because that upgrade is more difficult. Microsoft is committed to making the developer experience on Windows Vista as simple and productive as building application on Windows XP is today. However, Visual Studio 2003 or earlier would require many changes that make that experience worse. Customers will find that upgrading to Visual Studio 2005 will not only improve their developer experience but make developing on Windows Vista easier.