I think Wikipedia (not Wikileaks) only provides readers general information. I don't know how general is really general in people's views today ?
I think famous people do have the right to ask for specific information about them to be deleted off a web medium if they think it violates their privacy too much at some point; and usually this will be brought up to court and in most cases the rich famous people have never lost.
First of all, they can edit the wikipedia entry by themselves (or rather hire someone to do so, if they are famous the can afford PR agency, don't they?). You need to go to court only if things escalate into an edit war.
There are many known cases where persons tried to manipulate their own page in a way that is clearly against Wikipedia rules, many more borderline cases, and probably even more cases where the edits were so small that they didn't get noted.
It is not against any law (in general - you can write illegal things of course, but those tend to be negative so people don't write them about themself), but it can be against Wikipedia rules.
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