I opted out of IBAs as much as possible as soon as I had the option. But with this new reporting feature I opted in to see what the numbers really looked like.
What surprised me most of all was how few IBAs apparently get shown on my site. The number runs around 1% of ad requests.
They do seem to pay somewhat better, but there are so few it doesn't make a big difference.
It's also interesting to see how large the variance is in what the pay per click. Some under a dime, others for several dollars.
Do IBAs pay on a PPC basis, or PM, or both, or could it be either/or?