freejung - 5:59 pm on Sep 29, 2011 (gmt 0)
they contain hidden text (which is fairly normal for rich snippets)
I'm not sure this is a good idea. I think they would prefer that you just mark up the visible text, not add a lot of hidden text unless you absolutely can't help it. From schema.org:
More is better, except for hidden text. In general, the more content you mark up, the better. However, as a general rule, you should mark up only the content that is visible to people who visit the web page and not content in hidden div's or other hidden page elements.