Very out of topic but, is lena.jpg still acceptable? I mean, tech industry is getting better at inclusion but come on, are we still using that crop from Playboy?
Considering that Lenna herself is fine with it, I'd say so. (Unless you want to deny a woman the right to permit the use of her own body for aesthetic, erotic, or academic purposes, which is the logical if ironic outcome of some schools of feminism.) The problem with the Lenna imagery isn't political correctness, it's the fact that it's a crappy scan from a magazine that always had crappy photography to begin with.
Not doing something you are permitted to do is somehow denying their right to permit? It's nice of her permitting the use, however her permission doesn't force us to use it. By the same logic, it would be perfectly okay use goatse image if the guy permitted it, right?