Some of the very old ones (pre XP) might not work fully on Vista, but basically if the skin has XP parts (startmenu, taskbar) then it should work fine on Vista.

If you find a skin that does not, please let us know so we can look into why it does not work.

I hope you meant ObjectDesktop.  And as an aside, ObjectDock is not part of ODNT.

XP themes on Vista work fine IF they follow certain design parameters...if a theme follows basic XP design it will translate pretty well...get a bit outside the box skinning wise and they work...they just dont look good.  

Winc needs a Vista compatible WB section...None of my themes work well with Vista,with the possible exception of tore up XP...because it is modelled directly on XP...

til wb and skinstudio versions are updated to Vista specific specs...all skins will be a bit of a compromise...notice all new compatible skins folllow certain design similarities...simplicity and color that works with that horrid Vista toolbar.(bluish)