I addressed it squarely. Advertisers don't get information from Google, but don't complain (much) because Google is so effective at targeting.
Yawn. http://adage.com/article/digital/amazon-apple-catch-a-break-madison-ave/291724/ "Apple might come out ahead of its competitors on data, if it would share. "It's one of the best in terms of data quality and accuracy but I think Google is a little more open," said Dan Grigorovici, co-founder of mobile-ad firm AdMobius, "
I repeat: Apple has better data, and Google shares more of it.