Many people still think Apple is a "one-button mouse" company. Is it because the mighty mouse offers no physical cues to the buttons? That’s what David Morgenstern at ZDNet suggests: Is Apple’s Mighty Mouse Too Smart for its own Good? There are actually four buttons, not counting the scroll wheel: two at the lower sides and two on the top, which are differentiated left from right using capacitive sensing (see Apple’s page on Mighty Mouse design).
The Apple TrackPad has a similar issue. There’s only one physical button but you can control-tap or double-tap to get right-button functionality. Still lots of people comment on it having only one button.
I doubt many Mac users get stuck because of this, but it doesn’t help shed the "one-button" myth. I use a mighty mouse on my mac at home and like its design, except that the right pinky button is far too easy to accidentally click. (I never use those two extra buttons anyway, nor have I ever felt the need to use the extra buttons on Microsoft or Logitech mice.)