AJAX for SEO Friendly Collapsible Copy 
Text has really limited what designers can do and recently one of the design guys where I work was asking about using AJAX to create collapsible content that existed on the page and was displayed without refreshing the page once a user expanded a section. The question is… “Is this considered Black Hat, will the content be indexed, and will Google penalize you?”
The Idea behind the strategy is to use the copy you want as a text based include. The included file is not hidden using CSS or placed behind anything or the same color as a background. Using AJAX and Javascript, you choose to display the copy only when a user hovers a selected text or image.
What I know to be true is Search Engines have a Very difficult time understanding Javascript and even more when it is tied in with AJAX. From a search engines viewpoint, the copy in the include file will show as being visible in the code and on the page.
I wouldn’t not consider this black hat because you are showing the copy on the page without having to go to another page or even refreshing the page. The copy in the include file is being displayed on the page it is intended for when a user chooses for the full copy to be displayed.
This would allow for designers to be a little more free with their design if they could collapse copy into expandable sections on hover. I know CSS has a similar div:hover function but search engines have the ability to see that the div is being hidden until it is hovered.
Does anyone have experience or more knowledge in this area. I admit that I really don’t know too much about AJAX and want to hear some advice and get this information out to people that could use it.
Thanks,
Brad Henry