handsome_rob - 9:48 pm on Feb 6, 2007 (gmt 0)

From AdSense TOS:

In order to prevent user confusion, we do not permit Google ads or search boxes to be published on websites that also contain other ads or services formatted to use the same layout and colors as the Google ads or search boxes on that site. Although you may sell ads directly on your site, it is your responsibility to ensure these ads cannot be confused with Google ads.

Since YPN ads look strikingly similar to Adsense ads, I have to wonder if changing the colors of them would be enough to keep you clear of TOS violations. If so, how different do the colors have to be? Are these considered on a case-by-case basis? I was always under the impression that it was simply not allowed.