The snippet I posted enables the current tab highlighting in a custom navigation menu. It wasn't working beforehand, not sure if you were expecting it to. The URL was updating with each AJAX page load but the highlighted nav tab (which is set via the .current-menu-item class) wasn't updating.
So my snippet basically removes the class from each nav li and then applies it to the li (and/or its parents) which just triggered the ajax load. Hopefully that makes sense.
As for the nivoSlider... My particular reload code looked like
// DROP YOUR RELOAD CODES BELOW HERE //
..... followed by much more custom JS from all over my site.
Thanks again for everything, Dean!