I wasn’t able to get to the press conference after all–too much prep to do before heading to the X Prize Cup on Wednesday. But two of my editors from Popular Science went to the annoucement of Peter Diamandis’ latest venture, and I’ve gotten the scoop from one of them.

Diamandis is starting a rocket racing league, like the Indy Racing League (IRL). The first event will be held next September. Teams will race rocket planes based on the XCOR EZ Rocket design. Races will be held around the U.S., and then the top teams will face off at the Reno Air Races.

Initially XCOR will build 10 rocket racers. My editor tells me that these babies will cost $1 million each, so that will be a nice boost to XCOR’s finances. I’ll find out more when I see the XCOR folks at the XP Cup.

These rocket racers will not leave the atmosphere. In fact the EZ Rocket’s ceiling is 10,000 feet, according to Aleta Jackson at XCOR. Eric says that the rockets can only burn for up to four minutes, though they can start and mid-flght. Once they burn through their fuel, they’ll taxi in for a quick, auto-race-style servicing, during which they they’ll be refueled.

The significance of this as I see it isn’t whether or not these planes will reach space, but that the races will further the technologies needed for safe, routine spaceline operations.

Engines that can start and restart mid-flight, vehicles that can be quickly refueld, not to mention be reused, and are safe enough to operate around crowds–all of this will help the emerging commercial spaceflight industry.

MSNBC’s Alan Boyle filed this report after the press conference.

The Rocket Racing League launched its Web site today.