A power user, if I may take you seriously for a moment, is generally people who populate slashdot. They are people who know more than ctrl-c and ctrl-v to copy and paste. They might be aware they're using a Macintosh, and therefore substitute a command key for the control. If you ask them to press the 'print screen' button they don't look at you blankly. They've heard of it, even if they've never seen it. If they're a Macintosh user, they'll never see it, but nevertheless they know enough to tell you they have no such thing.
To check if you're a power user is quite simple. Do you control the computer or does the computer control you? Does the machine before you bend to every whim you have, or must you constantly think before daring to press return? Do you even know what return is?
When someone says captcha, do you jump?
Enough with the jollity. Power users are people who control the computer. The computer is their tool. They make it do their whim. Ruthlessly. That's being a power user. I'm one, and I guess you are. Your Mom isn't.