I used to be a big proponent of infinite scrolling, but it breaks down the second I want to send someone a link, or for that matter resume later on where I left off. It also tends to break the "back" functionality, good auto-scrollers will somehow save where you are at but the browser still ends up loading all previously scrolled through content and there is a delay until the scroll bar jumps down to where the user last left off.

It also does not allow me to easily link to a results page. Scenarios like "check out these mid-range priced items here" where I linked to page 4 of 8.

Now having pagination be AJAX based so the entire page doesn't reload unnecessarily, that I am all for!