AdSense silently adds a 90-day time limit on AdSense referrals. A thread over at DigitalPoint points out that Google AdSense has quietly added a new term to all AdSense referrals generated by a publisher. They have now instituted a 90-day time limit on that referral, meaning a referred publisher must earn the $100 within the first 90 days, before the referring publisher is eligible to earn that $100 for a completed AdSense referral.
Google uses the asterisk trick at the bottom of the Referrals page.
Google AdSense begins rich media beta test. Google AdSense is moving beyond the traditional text and graphical advertising to rich media, including interstitials, expanding ads and floating ads. AdSense began contacting publishers last week to be involved in the rich media limited beta test. Floating ads are ads that either stay on top as the page is scrolled, or ones that "float in" from the side of the page to the center of the page. Expanding ads are those that require user interaction to expand, either with a mouseover or a click. Interstitials appear when you click through to read a page, and before they will show you the page, you are bypassed through to a full page ad that you must view before seeing the actual content you were wanting, often by having to click a link on the interstitial ad page.