Evan-
Wiki is an exercise in trust. It's finding out
that if you open the
doors and let everyone in, 99% of them are going to be good-hearted,
hard-working, and well-meaning. And you can collectively deal with the
other 1% quickly and effectively.
More like 30-40% for anonymous users. Check RC on En: occasionally. The
simple fact is that most vandals, crackpots and abusers are anons, and
that "minor edit" is a tool that is easily abused. It seems fairly obvious
then that it's a good idea to limit that tool to signed in users.
Regards,
Erik