Itwon't get the prerequistites right if your 2008 project uses the 3.x framework, otherwise MSI files don't care what tool was used to build them. If you're installing anything into the GAC I'd make sure that works ok - I think it should work alright -VS 2005 will need to get assembly attributes from your VB 2008 assemblies but it's the 2.0 CLR underneath.