As you know, the Google AdSense ad balance tool has had its share of issues but those issues now seem to be back now and now that it is back, Google is adding more to it.
Google announced they are adding ad experiments to the ad balance tool. Google said:
Ad balance is a tool that allows you to reduce the number of ads shown by displaying only those ads that perform the best. You can now run experiments to see how different ad fill rates impact revenue and ad session lengths. Try it out and let us know what you think in the comments below!
Here is a screen shot of it:
Of course, those publishers who have spent time playing with the tool back in the day are a bit doubtful this will add any benefit based on the history of that tool.
A WebmasterWorld thread has one publisher saying "With all the ongoing insanity with AdSense now is a great time to roll-out new features [insert sarcasm]."
Forum discussion at WebmasterWorld.