This is us :) http://perfectaudience.com Really terrific to see folks appreciating the time we spent slaving over the billing system and trying to make it not completely suck. If anyone on HN is curious about retargeting, especially on Facebook, where low CPMs are plentiful, drop on by!
Is PerfectAudience going to look into CPC billing in the future?
Can you explain why CPC is important to you?
If we did CPC pricing, we'd still be buying the inventory on a CPM basis. That means we'd have to develop an algorithm that determins what CPM to bid based on your CPC bid. To make sure we don't lose money on it, we'd have to add some safety margin in there which ultimately means you're paying more.