Ausiello reported on October 7th that we'll see Simon soon. (For very mild spoiler, click the Read more...)

Quote:

Question: Wasn’t Dominic Monaghan supposed to appear in the second FlashForward episode? What’s the deal exactly? —Frenchy
 Ausiello: The exact deal is that he’ll turn up briefly next week.

Next week. So, does that mean episode four?