Since January, SpaceX's heavy-payload Falcon 9 launch vehicle has stood 180 feet above Space Launch Complex 40 at Cape Canaveral, undergoing ground-systems tests in the run-up to its first test flight. The reusable Falcon series, named for the Millennium Falcon in Star Wars, has nine engines that provide more than a million pounds of thrust. Last September, the smaller, 70-foot-tall Falcon 1 became the first privately developed liquid-fueled rocket to orbit the Earth.

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Another advantage F9 has over Ariane 5 is that it's designed as a human rated launch system from the beginning.
Yes Ariane 5 was designed to carry Hermes but this was canceled before the LV was finished so the man rating requirement was dropped.
It also can loose an engine on the way up and still complete it's mission.
The first launch vehicle since the Saturn IB and V that has true T+1 engine out capability.
from Kent, WA
Falcon 9 is a great success story. I have never like non-throttleable solid rocket booster systems for the same reason that my father hated and feared the JATO bottle system when he flew on PBY seaplanes during W.W.II. JATO stood for Jet Assisted Take Off but basically the JATO bottle was a strap-on rocket put on lumbering seaplanes so loaded with fuel for long-range missions that they could not otherwise get out of the water.
The JATO bottles had lots of power and just blasted the over-loaded, under-powerered seaplanes out of the water sure enough, but once you lighted the rockets off you were damn well going for one hell of a ride and the system was extremely intolerant of anything at all going wrong with anything else.