We are putting a huge effort into ensuring that applications that run on Windows XP will run on Windows Vista - but at the same time Windows Vista represents many significant changes and therefore there will be applications that do not run fully (or at all!) on Windows Vista.
If you are an ISV (especially a UK ISV - lets make sure we rock on vista!) then this is especially important as one product will impact so many desktops in so many homes and offices.
Please... start thinking about Windows Vista now. We are pulling together great resources for Application Compatibility on Vista and are looking for increased involvement from ISVs.
Please do contact me if you are a UK ISV and your app works fine on vista OR does not work fine. I'm trying to build a better picture of how this impacts our UK ISVs. Thanks.