RSS Advertising This is two-day-old news by now, but in case you missed it, we just announced than we – Return Path – are partnering with Feedburner to take RSS advertising to the next level (coverage here, here, and here). As you probably know if you receive my feed or other ones, Feedburner has been doing some experimenting with ad units at the bottom of feeds for months now, first using Amazon and more recently Google AdSense to serve up ads. And as you may know if you look at ads closely, neither of those services has done a great job making the ads truly relevant. I can’t tell you, for example, the number of times I write a posting…