re: "Who is X-CAD?"
I haven't a clue.
The links (from X-CAD's site, mind you, so keep the salt handy) to columns and blogs by people who seem to know the business all imply that the people behind X-CAD have instantly recognizable names within the industry... and everyone is playing along with the secrecy game.
I'm certain that I won't recognize the names, after they've gone public -- I'm not "in the industry" -- and frankly, my dear, I don't give a damn, as long as the product works without slowing my machine to molasses.