Aviation buffs: Need some info regarding Cessna Citation X's speed

Factual Questions
1

I’m trying to find out about the ranking of the Cessna Citation X with regard to its speed. I’m finding some conflicting information about it. As far as I can tell, it’s not the fastest civilian jet ever, since the Concorde is significantly faster. But how many other civilian jets are faster than the Citation X? Any how many of those others are still in use? Wikipedia says it’s the third fastest after the Concorde and a Tupelov, and the fastest in current use since both of those planes have been retired, but Cessna apparently claims it’s the second fastest after the Concorde. I’d like to know its ranking for certain.

Also, the Citation X is being called the “fastest business jet” in history. First of all, is “business jet” an official classification? If so, is the Citation X indeed the fastest in that class?

Lastly, is the Citation X ranked the fastest in any category?

Any citations for information would be greatly appreciated. Oh, and sorry for the scattered and disjointed post.

2

It’s pretty well established that the Citation X is the fastest corporate jet. And yes, corporate jets (or bizjets) are considered an actual category of aircraft.

See http://www.airliners.net/info/stats.main?id=166 for some stats.

As for the claim that it’s the fastest civil transport, that’s still a matter of debate. Some claim the Boeing 474-400 is in fact faster. It does have a higher max cruise speed on paper (507 knots as opposed to the Citation X’s 504).