It is about time. Small engines like Bowsearch have had this for over a year. But Google maintained that it would create havoc, some advertisers would never get any traffic and the big ones would be fought over by the big advertisers and the little guys would get pushed out.
Welcome to the real world of business.... and I guess the IPO and a solid period of growth moved Larry and Sergi into the right clubs and at the right dinner tables where through the smoke (allowed or not allowed - these guys do it anyway) of cigars the conversations of business methods and how real wealth is maintained slowly made them aware that the illusion of high standards are fine for organic search. But if you are going to maintain the lofty ideals there has to be a sweat shop somewhere behind the curtain.
This is business. The big guys always get better service - unless the sellers have deep pockets and want to build on the short supply methods. Google seems to be adapting well to the real world of modern business... keep it up and the portal is right around the corner.
Hell, I would almost be willing to bet that if Google has 3 bad quarters of decreasing stock prices that they would start selling ads on the homepage!!!