I think they make some good points. Bitcoins is NOT for the faint of heart. This is the rocket ship of trading for the last 3 centuries ... you have got to have balls of steel to be riding this pig!
Early adopters are either going to get rewarded richly for their risk appetite or royally screwed.
Bitcoins are fascinating, for mathematicians, economists, traders, investors, politicians, regulators, and anarchists. And while watching the currency develop is entertaining, the experimental currency is no place for serious investing given the risk versus reward. Attempting to trade in established currencies is difficult enough.
They may not think it is "serious investing" but ....