Wife runs a not-for-profit. This is brilliant. My perception is that petitions don't often accomplish their stated goals, but what if the side benefits of gauging interest, drawing light first-step commitments, and collecting contact information accrued to your org instead of an activism-feelings-aggregator like change.org?
That may come off as cynical to people, but as a petition-signer, I'd rather get followed up a couple times by an organization actually working on something I care about (and given a path to act a little more on my caring, even if it's 'come to this event' or 'give us money') than followed up indefinitely by change.org, who cannot seem to guess well at all what sort of petitions I'd like to support.