Groan. As if JotSpot's integration (and death) within Google weren't bad enough, FeedBurner's integration into the Google system has been awkward as well.
They changed the hostname hosting feeds from "feeds.feedburner.com" to the ugly "feeds2.feedburner.com." Inelegant, but workable.
Subscriber tracking support has been off, and it's been suggested that it take a week for all subscribers to be counted again; strangely enough, it's Google Reader stats that are missing. Confusing, but tolerable. (Can't the two parts of the company talk to each other?)
But most annoyingly, FeedBurner's site analytics features have been removed, making it impossible to gauge combined feed and site aggregate traffic. This used to be one of FeedBurner's best features. I understand that there's likely an internal imperative to reduce duplication with Google Analytics, but the obvious solution would have been to offer some kind of linkage between the FeedBurner and Analytics products.
As it stands now, users have to log into one system, then log into another, and manually make a best-guess calculation of reach. This is a major step backwards. I realize both FeedBurner and Google Analytics are free services, but I've grown to expect a much better end-user experience from these teams.