I personally think this is great (especially as a teacher), and have already thrown in a contribution this morning learning of the site. I present to you my Tylosaurus/Taniwhsaurus, complete with new and improved tail fluke (this is based on direct input and collaboration with a Mosasaur expert I might add).
As this was remarkable easy to create, I set a challenge for everyone who reads ART Evolved to create at least one silhouette for PhyloPic a month. With at least 60 known contributors to our site, that adds up to 700 new critters on their site a year!
If you're interested in helping, but don't think it would be easy to create these silhouettes, I can prepare a quick and easy tutorial on just how, well, quick and easy these are to put together. Let me know if you'd be interested in the comment section.