Philip Verleger, an energy economist with the Brattle Group, a consultancy, observes that successful central banks are secretive about when they will intervene in the foreign exchanges.

ECONOMIST: Oil

"The Facebook listing I've seen as being similar to the Google listing, which had a similar competition between the exchanges, and a similar win for Nasdaq, and a tremendously successful IPO for both, " Mr. Frankl said.

WSJ: Facebook to List on Nasdaq