The money aspect sounds super perverse, but we think of it as paying a fee for a service (the graphs, reminders, etc) that happens to be waived if you never need Beeminder's kick in the pants.
It supports going by issues, which is better, but how about counting additions/deletions?
I think minding commits isn't as bad as it could be theoretically though. I feel like pride is sufficient deterrent not to do pointless commits. And general pressure for more fine-grained commits is probably valuable.
Wait, I guess this doesn't support private repos.
I assume you poll Github on some timescale? I noticed that Beeminder took around 24h to see my commits.
Right after I finished this we noticed that we could also do this with a post commit hook, so we're planning to implement that as well.
We haven't gone quite so far as to count the actual creation of the bugs towards our goal though. :)