Alex Marvez is reporting that the Lions-Steelers game will resume at approximately 9:45 p.m. As long as there is no more thunder and lighting, the game should be good to go at that time.
When the game does get going again, the final 1:31 of the first half will be played. The weather delay is essentially serving as a halftime break, so the second half will begin immediately after the second quarter comes to an end.
Hopefully the weather cooperates so they can get this thing going without any more problems.
UPDATE: It's now 9:55 and the game is still not going, but the Steelers' TV network showed people fixing the field, so I imagine that is the holdup right now.
UPDATE II: The players are warming up right now on the field. Play should be resumed shortly.