"it was also an experiement to see if...pointed criticism worked on Twitter"

Hmmm: "if Twitter sanitized searches, that would make the site a more fake and less democratic place than it initially appears to be. Here we thought we were meeting bigshots in a virtual public square, and really it was maniuplated like the Truman Show."

Also, if Twitter does take special measures to shield celebrities from nasty comments, it's the perfect business model for our times.