true_INFP - 9:05 pm on May 2, 2009 (gmt 0)

Back in 2003 when I started, in my niche there were only about 6-7 of us [publishers]. Now, I couldn't even tell you, there appear to be hundreds.

Do you think the number of advertisers has not increased since 2003?

And yes, I know that Google doesn't reveal the percentage paid to any individual publisher

Yes, and why do you think they keep it secret? Because of the competition? What competition? I don't see any. AdSense has no real competition. It's a near-monopoly. The only real reason I see is to be able to change the percentage without the publisher or anyone else knowing. If you see other (good) reasons, list them.