I'm working with a Community Server site theme that has a blue background and concluded that the out-of-the-box rating stars, while looking fine on a white background, looked downright crappy over the blue. So I rolled my own. Here's what they look like.
Pretty! If you look at the HTML generated by, in our case, the CSFile:EntryRating control you'll see
<span>
<img border="0" align="absmiddle" src="../images/common/star-left-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-right-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-left-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-right-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-left-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-right-on.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-left-off.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-right-off.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-left-off.gif"/>
<img border="0" align="absmiddle" src="../images/common/star-right-off.gif"/>
</span>
So we're working with half-stars that form a whole to support half-point ratings like 3.5. The Photoshop workspace below gives you a better idea of the images that comprise a row of rating stars in Community Server.
This is great. I can finally say I've written a 5-star blog post!