In the end you can't ask how much money will one lose over the next few years on their purchases without getting flamed a bit. I have seen one Pinsiders collection of roughly 30 pins. His avg. pin is probably 6k. If they all dropped in value over the next few years by even 1k each, I'm sure he and others like him would shit themselves,so to speculate this type of stuff to the very people who paid dearly for them is like trying to scare the know what out of them on purpose.
But fortunately for most people here, this thread has been hashed and rehashed many times, so no surprises, revelations or new speculations can be had here.