She doesn't have to change her old photos. She's just not going to use any more. Which -- well, I can imagine not wanting to have anything to do with Zillow in the future. Or to give them free advertising by referring to them for each photo caption. I quite like the idea that her future posts will say "Images from Redfin, a pretty awesome site that isn't threatening to sue me for using images for purposes of education, commentary, and parody." :)

But seriously, she won the most important thing: Her entire existing body of work is going to remain available.