Does this have anything to do with Google being able to index Ajax pages? I heard that Google was developing certain technology to better index Ajax driven sites.
They want to add anchors in long pages, pdf's, forum threads, ect., so when a search term(s) lies deep in a page, Google SERP's will have direct links to the searched content within the page. The idea makes sense, but when the important content above the fold is skipped, the reader may miss the point.