I couldn't agree more. If you're out to make millions, why not set out to be an entrepreneur and invent something that will get you there? Because the chances of actually thinking of an idea, producing it, marketing it and generating profit from it is incredibly slim, high risk, and who says you're working any harder than becoming a dentist?
If you want to make money then of course being a dentist is a great option, but why do you think we go through all of these years of schooling? Because it's safe, smart and will have a tremendous return on investment. Think of your friends who may not be entering medicine, in a couple years (granted you play your cards right) I can guarantee you will probably be making almost twice if not more than they are. I don't mean to sound negative, but I'm sure at that point you will be glad you stuck with it.
How is this possible? Well you will be the dentist so as one of the earlier posters said, it relies on your business mind. Yes you may be working as an associate (not a "work horse") for some time, but isn't that how everyone in the film and entertainment industry started? And now most of them are millionaires.
Yes there will be debt involved, but you have gained an education, which is invaluable and growing harder to attain in this society.
Granted if all else fails, you can specialize. The demand for a specialist is always high. Problem solved
Source: 8 dentists in my immediate and extended family...and then some
Good FAQ:
http://www.ada.org/1444.aspx