MP is a professional scoundrel who even calls Coinbase a scam without having any conceivable way of proving what he alleges. https://bitcointalk.org/index.php?topic=140484.0 Note he took icbit.se off his scam list because they paid him.
There have been plenty of scams in Bitcoin and there will continue to be. This is why some in the U.S. push for regulations because even though regs won't stop crime it will create more reliable and accountable services. Pro tip: this is essentially why strict Libertarianism doesn't work.