Thanks for the recap, I enjoyed solving this when it came out! I'd be interested in some more numbers if you're willing to publish them. How many people completed each level, how many people attempted it. How much email correspondence you received from people who completed the entire thing, etc etc.
I'll echo the thanks. It was fun contest; I wish there were more programming challenges as they force me to think about something that isn't work-related. Usually I have to stick to Stack Overflow for that, though.
Thanks again Greplin for putting this on! Like other people said, I had a blast doing this on a Friday night, and definitely would love to do it again (even without the possibility of a job :) ).