Problem with Rating Plugins

After upgrading to 3.1 (and also upgrading my theme), my ratings plugin (WP Post Ratings, which uses AJAX) no longer works. I can mouse over the stars, but it no longer “fills in” the stars as it used to, nor displays the rating text to the right, and finally, it won’t let me actually rate anything. Example: https://www.thatfreelancesite.com/2011/02/19/demand-media/

I tried installing a second ratings plugin entirely (Five Star Ratings)– one that uses shortcode embeds rather than embedding in the theme –and I have the same problem, all I get is empty stars that I can’t do anything with. Example: https://www.thatfreelancesite.com/2011/02/26/gawker-media/

Is anyone else having trouble like this with ratings plugins, or with AJAX plugins?