Text would not have been redundant: it would have allowed users to see everything that was new instead of having to crawl over the site looking for new stuff. Eg: I have to check three or four possible locations to see if I can now see who my friends are reading, instead of checking a list of new features.
The evidence that text wouldn't have been redundant is even on this thread -- poster asks what's new, is answered in a sentence. A line like that accompanying the video, or even in a separate post, would have been of unquestionable utility to users.
Or, hell, Apple software is pretty self-explanatory too. Perhaps their minimalist "bug fixes" change notes are sufficient after all?