I'm one of the people behind Scratch <http://scratch.mit.edu>; and I can tell you that Automatoon is seriously cool. I can already see a lot of our users would like your tool. Kudos to you for empowering amateur users!
I am a bit confused about the pricing model. Why did you decide to charge per creation rather than per month? Who is the expected audience? Again, great tool.
Most of our audience is just people who play with it because its fun and tweet/email it to friends. This is how we hope to get publicity. Our secondary audience is web developers who need just a little bit of animation for a site and don't want to lose weeks becoming proficient in Flash/ToonBoom and paying for all the pricey authoring tools. We hope the second category can expense the premium cost for their projects to clients and won't mind paying a reasonable per-project price.
However, we're certainly open to other pricing models... We just figure since the "iPhone App" era people are more comfortable paying one-time fees instead of signing up to a renewing prescription.
I see, but the iPhone apps people often pay for tools they can use to create multiple artifacts. Maybe it'd be best to charge less per creation (like $1) and remove more features from the free one (e.g. animations could expire in 1 day and can't be downloaded).
The reason we don't want to "cripple" the free version is because we have low overhead and can afford to make low revenue at the outset- We'd rather focus on capturing a larger market (though it's always hard to say what the market really is with a new product)