This is the private company that wants to mine asteroids. They cancelled launch because pressure was a little high in one of their chambers. First private launch to dock with the International Space Station with a billion dollar NASA contract on the line and potentially ferrying astronauts up there in a few years, no kidding there was pressure. Technical glitches are understandable though, it is rocket science.
You can watch the next step in space exploration live on Tuesday May 22; 12:44am PT, 3:44 ET, 7:44 UTC at http://www.spacex.com/webcast/