Thanks to the legal battle between Google and Oracle, several details of each company's internal operations have been revealed to the public. In addition to photos of the original Google Phone leaking earlier Wednesday, information about Android OS revenue has been revealed in a series of presentation slides.

The Android quarterly report slides show that -- as was suspected by many industry analysts -- Google made more cash on Google Ads through Apple iOS than it did through its own Android OS. The slides indicate that between July 2009 and June 2010, Apple was the highest source of mobile ad revenue for Google by a large margin. Even by the time Android became the second-highest mobile ad revenue source for Google, the operating system was only generating a small fraction -- roughly half -- of the ad revenue that Apple iOS was.

Tech blogging site The Verge points out that Google had forecast that by the end of 2010, it would have activated 40 million Android-based smartphones that would pull in $278.1 million in revenue. Of the projected revenue, $158.9 million would have come from ads while $3.8 million would have come from app sales. Google expected the gap between ad revenue and app sales revenue to widen by 2012, projecting $840.2 million to be made from Android mobile ads and $35.9 million to be made from app sales.

Projections may have changed, however, after the launch of Google Play, which replaced the old Android Market. The slides indicate that Google had recognized it was behind on music, video and books, which is something the new Google Play store is supposed to address. Google projected it would generate $738 million in music sales revenue in 2011 and $1.5 million in 2012, which seems to be a grand expectation for a service that's still secondary to other music streaming and MP3 purchasing software.

In a note to The Verge, Google was sure to indicate that the numbers in the slides were outdated. Here's what they had to say:

The discussions in the documents date from 2010 or earlier, so don't represent current thinking about our business operations. Our industry continues to evolve incredibly fast and so do our aspirations for our various products and services.