I don't have Vista handy to check the patch. 

Ideally, win32_ver() should be patched to return proper values for Vista directly from the registry. Would be great if you could provide a patch for this as well.

However, in some cases _syscmd_ver() will still be used, so the patch is fine. Please add a comment explaining the problem and also add a check to set release to 'Vista' in case the version starts with '6.0'.

Thanks.