This plugin allows blog admins to create a revenue sharing program utilising one of the many advertising programs out there.
That's a very good question. I've been working on a completely rewritten plugin for a long time now but I just can't seem to get the time to sit down and get it finished off!
You modify the Author Page and let your users know that you're using Adsense. You check one of the custom fields and give it the title of Adsense Slot ID or something similar. Then the author will put their publisher ID and slot ID information into their page. Remember to put your own defaults in the custom default slots so that your own ads show properly. Check out the manual (included with the zip and also linked from the plugin options page) for more help on setting up Adsense.
Yes you can put any HTML code into the boxes. PHP won't work though. You could use this plugin to insert a widget that displays the author's picture or some other author information. It'll still rotate with your information unless you set your admin percentage to 0% then it'll just be for authors. On the front page if you randomise ads then all of your author's information/picture etc would be rotated.
You can use the Members plugin to create new user roles and then check out the options page again.
You can contact me using the forums here or by emailing me email@example.com.