The dangers of Wikipedia and defacing entries

I am a big fan of Monica Seles, the tennis player. I was reading this afternoon her Wikipedia entry when I noticed someone had written nasty stuff in her entry (see photo below).

To me, this is the danger of Wikipedia as a self-correcting informational mechanism. Granted, I fixed it as soon as I found out (and as soon as Gregg told me I could edit without even being an editor). Still, it’s scary to think that anybody can deface the Wikipedia entry of anyone.