Once again Patrick has made me think twice about what I can and should be doing with my webapp customers. These show-and-tell type posts are worth a lot more than face value...
Looking at the promos, it looks like he got 15 (mini site) + 15 (email) sales, which appears to be around $700+ in revenue. Percentage-wise it seems notable, but in absolute numbers, I wonder if the time could be spent better in other ways.