From Google's official AdSense blog, earlier this morning:

Today, in the spirit of greater transparency with AdSense publishers, we're sharing the revenue shares for our two main AdSense products - AdSense for content and AdSense for search.

The breakdown: Google takes 32% off the top of its ad sales in AdSense for publishers (the AdSense you put on your site); 49% for search partners. In other words, over a third of the advertising money that feeds into Google ad systems, which are everywhere, end up with Google. Google isn't currently saying what its cut is from ads in mobile apps, feeds and games, but I'd imagine it's in the same ballpark.

At any rate, as we see Google more and more as the company of Android, and Chrome, of phones and of airy fairy future gadgets, it's easy to forget: Google's power in the gadget world comes from their money, and their money comes from advertising. We readily talk about Google and Apple and Microsoft in the same breath and with the same terms, and rightly so—they are competing more and more directly every day, and the conflict truly is a collision of giants. At heart, though, the youngest giant is a totally different species. [Google via Metafilter]