Did you check Vista UX guidelines? In particular Command Buttons.

>I'm trying to give an application a more modern/XP feel so I have been trying out the Hot tracking special effect on the controls.
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>Is there any guideline specifying when buttons should be hot tracking and when not? It seems to look right on a toolbar, but I'm not sure I like the look on a form. What do you all think? Is this mentioned anywhere in the Windows UI guidelines?