NOTE: this may not apply to the most recent versions of the plugin
Just to add a warning. We have a WP 2.0.5 site with an earlier version of the plugin installed. We found that Google was not indexing our site. After a lot of research and investigation, it turns out that the problem was caused by WP-PostRatings. I think we are using version 1.02.
Right, I realise it is old, as I said in my post. Glad it was fixed in your updates. The reason I posted this here was to help other people who may come across the same problem. It is not intended as a criticism of your plugin.