Actually, I think being a millionaire IS defined as having assets of at least one million dollars. The number of millionaires has increased greatly of late, so apparently it's no biggie anymore. Now, if you get to be a billionaire..... you've arrived!
Check out this article:
Report: Number of U.S. millionaires jump - Jun. 9, 2005
Report: Number of U.S. millionaires jump - Jun. 9, 2005