AdSense for Feeds was finally released, I tried to add ads to my original feeds which were burned by FeedBurner. FeedBurner offers AdSense settings, but you need to put the ad codes to your blog by yourself, and it's not working for me, because I can see the ads not just in the feed, also on the blog, I don't know why.
And now you can setup AdSense for Feeds in you Google AdSense account. But I found that you must create a new feed with Google, you can't use your feed from FeedBurner,...