Well, live and learn, I guess. I peeked under the lid (carefully) -- couldn't see any signs of kraeusen, but hard to tell, what with all the hops and all.
If I don't see anything by the end of 24 hours, I plan to take the layer of hops off the top (sanitized spoon, of course) and sprinkle my 2nd packet of yeast to see if I can jump-start things. Any better ideas, or do I just need to be more patient?