I'm left handed and learned to use the mouse with my right hand early on. I'd say it has saved me from a lot of headaches. I am able to use these nice Logitech mice with my right hand and don't have to worry about continually annoying everyone by moving the mouse to the left side and wanting to switch the two buttons (it actually annoys me when other left handed people do it).

I suppose I may just be more ambidextrous than others, but if you're able to make the switch, it's worth it. Then again, I'm not sure that I'll be able to use the Wiimote with my right hand as well as my left (doubtful).