I was just catching up on that earlier today. Anyone with a Webmaster Tools account could remove a URL from the Google index - even on other domains. That's a security hole you could drive a truck through!
But, wouldn't WMT list urls removed by others? That one is a real serious issue...how on earth can you write a program that allows you to remove urls from a domain for which you are not added as an owner? simply BS...
Goog is coming through logs no doubt to look for those fun loving people ;). Payback gonna be a b*tch.
There have been some reports of people being deindexed and weeks /months later desperately asking for help on Google support forums. Shows the need on top of things or everything can be gone in one shot.