Is there any example of a site having their dynamically generated* disqus comments indexed by google? Disqus is probably one of the most common form of ajax-generated content on the web, so if this were the case that googlebot was actively indexing dynamic content like this, I would expect to see disqus supported.

* disqus has an API to allow you to display disqus comments serverside, so some disqus implementations - think mashable is one - will have comments indexed without the aid of Javascript.