AdSense for feeds is going away on december 5th

"After carefully evaluating the product, we’ve decided to retire the AdSense for feeds product.
The process will happen in two phases and your account will be affected, depending on your usage of the product. To check whether you’re currently generating any revenue from AdSense for feeds, run your “Products” performance report and review the listed products for recent data for "AdSense for feeds."

Although AdSense for feeds is going away, this change won’t affect any other AdSense products you’re currently using or the availability of the other products to you.
Payments

Your AdSense for feeds units will continue to accrue earnings until December 3, when they will stop showing ads on your RSS feeds. As of the last day of December 2012, your earnings will be finalized as usual. At this point, one of the following will apply:
If your earnings exceed the payment threshold, your account will be sent for approval for payment, and payments will be issued through the standard AdSense payment process.

If your earnings do not exceed the payment threshold, but you use other AdSense products, your AdSense for feeds earnings will be accrued toward payment in a future period when your AdSense account does exceed the payment threshold.

If your earnings do not exceed the payment threshold and you don’t use other AdSense products then the amount of accrued earnings from your AdSense for feeds units will remain as a balance in your AdSense account for as long as your account is open.
Reports and earnings

Reporting on AdSense for feeds and corresponding channels will remain available in your account. Even though you will no longer be able to access AdSense for feeds settings and channels, you will be able to see historical performance of them on thePerformance reports tab in your AdSense account."

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