Of course... if either Nagle or Foo was confident in their predictive ability, they would've shorted btc at 5:1 leverage on Bitcoinica and made a fortune. They can still short if they're confident. But I'm guessing they prefer to make predictions without backing them.
If there had been Bitcoin options in June, offered by a counterparty strong enough to pay off if the price tanked, I would have bought some.
Bitcoinica is only a month old, and already their customers are complaining about troubles getting money out. I wouldn't deal with any options dealer who didn't have a contractual commitment to settle by day T+3. I suspect that a lot of people are going to end up holding the bag when the exchanges shut down.