Read from an article on CNN (http://www.cnn.com/2012/05/19/tech/us-spacex/index.html):

"This is not a failure," Shotwell (SpaceEx President) told reporters. "We aborted with purpose. It would have been a failure if we lifted off with an engine trending in this direction."

Perhaps that's PR spin, but I think that it comes from a very responsible position. Well said.