For goodness sake, I am typed in the C680 and you guys keep claiming that it is based on the Excel fuselage.  And now you have a link to an old and inaccurate story from Airliners.net that supports this.  The Sovereign uses the Citation X fuselage and nose.  The wings, engines, and empennage are different.  Originally Cessna was going to use the Excel fuselage and stretch it, but they did not. The airliners.net article is old and inaccurate.  Call Cessna in Wichita and ask them, or ask any C680 driver like myself.  The Excel fuselage has nothing to do with the Sovereign.