FeedBurner’s share is 35% of the net advertising revenue for ads running in your feed.
It is possible that your estimated monthly revenue may change through the month or after the month has ended, and you may receive less or more in an actual payment than was previously estimated or indicated by the total number of ads served. For example, advertiser auditing of campaigns may result in different results for number of ads delivered. In such cases, the advertiser may only pay the audited number, not the FeedBurner calculated number. This is one reason your initial estimates may differ from the actual payment. The details of terms associated with this payment schedule are laid out in our Terms of Service.