9/25/2006: When Momentary Blink resolves, the creature is exiled, then immediately returned to the battlefield. The game sees the returning card as a different permanent from the one that left the battlefield. Any counters, Auras, and so on are removed. Any spells or abilities targeting the creature no longer target it.
9/25/2006: Any "as this enters the battlefield" choices for the affected creature are made by its owner, not its old controller.
2/1/2007: If Momentary Blink is cast on a token creature, the token will not return to the battlefield, because of the rule that says a token that leaves the battlefield can't come back.