Feedburner is dead?
Google killed it without warning?
More:
Google Pulls the Plug on Feedburner by Lynette Young 10:51 AM
Update:
Not Dead Yet!
Known Issue: Subscriber Counts and Stats
Friday, September 21, 2012 | 9:26 AM
Issue: We have been encountering difficulties with our stats production pipeline for data representing Sept 19th and 20th, 2012. We are currently working to resolve the issue.