The truth is - none of us actually know the real power/earning potential of the MMPs. We do not know if the MMP is "for real" - yet. Yes, the USPTO has given the MMPs a nod but as wel all know, we have to see the proof in the form of big revenue.
http://thefagcasanova.wordpress.com/2009/10/11/the-greatest-inventions-never-made/