I was expecting to find a nude photo in the article about [[Kate Winslet]], which would be appropriate (out of context, misleading). However, the photo is a very tasteful nude shot from the film ''Titanic'', and is used to enrich that article's narrative about the movie - not to mention that it's a partial nude, with only a left breast visible.
I don't know the uploader's motivation, and I share your suspicion that many people might try to cause disruption by uploading such photos. However, the best response to that, in my opinion, is to have clear policies on the matter. Then the trolls can do whatever they want, and we just decide quickly how to deal with the matter. Such policies might evolve out of precedents like Autofellatio and this photo.
Erik