My buttons all have a highlight around them after I click them. This is in Chrome.
I mentioned this in a comment above, but it's worth listing as a separate answer for clarity. As long as you don't need to ever actually have focus on the button, you can use the focus event to remove it before it can apply any CSS effects:
$('buttonSelector').focus(function(event) {
event.target.blur();
});
This avoids the flicker that can be seen when using the click event. This does restrict the interface, and you won't be able to tab to the button, but that isn't a problem in all applications.