The notifications work from the lastvisit - if I visited the forum to remove a spammer but not read your thread, and then revisited again an hour later or so, then I would have missed the notification!
Here's the template I used:
Code:
<span class="button like">
<a href="javascript:;" title="{$lang->plus_post}" onclick="PostReputation.vote('{$pid}', 'plus', '{$uid}')" id="plus_link_{$pid}"><span>Like</span></a>
</span>
So basically, you can create a class that looks something like this:
Code:
div.postrep span.button.like {
background: url(../path/to/image/like.png) no-repeat;
}
It works a bit different here (the background is actually applied to the span element in the a tag) but you get the idea.