Yesterday the Google AdSense Blog announced that you will be able to make changes to your ads in the AdSense console and those changes will automatically be applied to your live ads without swapping in new ad code.
This new ad management feature means that your ad unit settings (such as colors and channels) for new AdSense for content ad units will be saved in your AdSense account every time you generate ad code. Then, if you'd like to change any of these settings in the future, all you do is make the update within your account -- you'll no longer need to manually replace the ad code on all of your pages. For instance, you can quickly change the borders of all your 300x250 medium rectangles from red to blue with just a few mouse clicks. Fancy! We hope that this new feature will help you save time and will simplify the process of optimizing your ad units.
This is going to be rolled out in the next few weeks, you will now when it is live when you see the Ad Setup page change. The page will look something like this:
There are two forums threads on this topic, one at DigitalPoint Forums and the other at WebmasterWorld. The bottom-line response is that publishers are thrilled with this announcement. It will save them so much time and headache.
This feature is great and should improve their ad serving speed, reduce their servers load, as well as reduce our served page file size -> better visitor experience.
Note: You will have to change your ad code once after Google implements this new feature. After that, you will not have to change your ad code to make changes to your ads.