Popover Not Showing

I’ve installed the latest popover plugin on a single site of my WPMU 2.9.2 installation.

I have placed content and checked the update settings, but no popover shows up on my page. I have tested it in IE 7, FF 3.6, and Chrome with no success.

Is there something about configuring the plugin that I’m missing? Could it be having a problem with WP SuperCache?

Thanks for your help.