What is Mangosteen?

If you haven't yet been approached by someone who wants to sell you a mangosteen drink, you may be soon. A Utah-based start-up selling a mangosteen drink called XanGo has become one of the fastest growing network marketing companies in history.

But is this craze justified or is it a tad premature? A reader recently wrote me with this very question. He asks, "Would you have any info on this mangosteen "cureall" that my wife is taking? I am concerned that it is just one more marketing scheme she has fallen for. Thank you." What is mangosteen and why are people so crazy for it?