I think you're right, I don't think it'll work on Vista as the older 126.96.36.1995 driver only ever mentioned Windows 7 support :-
I'd guess that someone just added it on to the description without checking, especially considering the 188.8.131.523 driver has no release notes yet.
For info I have had problems with this driver (184.108.40.2065) in a GMA 3650 equipped Shuttle nettop running Win 7 32bit. In some applications video had bad artifacts and in others the GUI flickered.
Solution I found was to upgrade to *.1077. Have noticed that *.1065 remains the latest recommended version for GMA 3650 - feel that this should be updated.