Integrate with RSS: allow creating a goal from an RSS feed
I don't know how you keep track of Beeminder blog posts, but an easy way to keep track of blogging and other publishing-type tasks (Twitter, Youtube, ...) would be to check an RSS/Atom feed and then count the posts / words / whatever.
Oh, and in the meantime, this is super slick: https://ifttt.com/recipes/86058 (An if-this-then-that recipe for sending a +1 to the Beeminder bot when a new item appears in an RSS feed.)
Update: Twitter is dropping support for RSS. Lame. I think we should support Twitter separately though: http://beeminder.uservoice.com/forums/3011-general/suggestions/3922831-integrate-with-twitter
I really like the idea of native RSS/Atom support. For any goal you could just paste in a URL for an rss feed and we'd just add a 1 to your graph whenever something new appeared on the feed. Beeminding your own blogging is the most obvious use case but as you point out, it could be much more general.