Jonathan Leger's AdSense and Yahoo Publisher Tracker fills in the niche that for some reason Google and Yahoo just didn't cover. Their click-through rate and revenue tracking systems are very weak and aren't very useful for improving your ad revenue. Whereas Jonathan's Tracker is simply amazing.
To mention a few of the advantages of the Tracker:
Besides the access to the Tracker, Jonathan also includes:
I suppose you can get most of the extras elsewhere but you get those for free, so one can't complain :) And the list of top paying keywords is a great thing if you are thinking to create new content - why getting paid 5 cents per click when you could get $20 and more?
Michael Cheney who makes about $20,000 a month with Google Adsense attributes a big part of his success to Jonathan's product.
I wonder if Google and Yahoo are going to provide anything like that. I suppose they create an opportunity for other people to get rich, but really if they empower their publishers to be more profitable, those publishers will bring more revenue to Google and Yahoo. Or may be I'm wrong...
Update: Jonathan's AdSense and Yahoo Publisher Tracker site is no longer available.
Things to Do to Improve Your Site's Google Page
Paying AdSense Keywords Hoax
to resurrect your AdSense account
Hillenbrand's Adsense Decoded Review