Yesterday morning, I noticed that the number of subscriptions for ProPR that FeedBurner is counting decreased by 400 between Sunday and Monday. I tweeted about this and several other people chimed in that they had experienced similar issues.

Dave Fleet reported that he’d seen a similar loss of subscribers to DaveFleet.com. Martin Edic, the Marketing Director at social media measurement service Techrigy noted that changes to iGoogle had resulted in the loss of a number of his RSS feeds. Luke Armour and Ryan Coleman both saw a sharp drop off in the number of their subscriptions to their blogs, Observations of Public Relations and Found in Translation. And Jamie Oastler tweeted that one day last week, it had appeared that subscriptions to Idealien had dropped to zero before bouncing back to their usual level.

Later in the afternoon, I tried to check my stats again to see whether they were still wonky. But all I was able to get was FeedBurner’s version of the FailWhale.

Unreliable stats. Service disruptions. Google acquired FeedBurner more than a year ago. With all those dollars on the balance sheet, you’d think that Google would ensure that FeedBurner performs as well as Google’s core search service.

Do you know what is going on with FeedBurner? Why isn’t Google investing in making it more reliable?