Google has released this video on adsense optimization and i personally feel that it’s the best amongst others i have known , and it should be, as it is from the giant itself ( Google ) .. Including ads placement techniques and color blending etc .
here is the video ..

Google has just added Google Apps Referral in Google Adsense. You will be credited $5 when someone clicks the referral ad from your site and signs up for Google Apps with a domain that has not already been signed up for the service.
If you want to configure your Google Apps referrals, you should login into [...]