Great job of selecting a pose that makes beautiful lines as well as catching the lights just right to produce thin outlines. It's a shame but I'm sure a lot of people will say it's not a "true" silhouette and mark it down.
#1
Hopefully you're not getting the same comments that I am, that the subject is discernible. There are some definite positives here; nice clean lines, interesting subject, good pose, but more importantly, different from the rest. It's not yet another silhouette against a sunrise/sunset.