I have to admit: I really don't understand the pinging hysteria. Everyone wants to be pinged, and I really wonder if everyone thinks that's the best we (as an industry) can do.
Don't get me wrong--our tools have pinged weblogs.com and blo.gs for years. But of late, there are more and more parties interested in receiving direct pings, rather than federating based off of the updates that weblogs.com and blo.gs have always propagated. 
And frankly, it just makes it wonder: it's a bit ridiculous to suggest that direct pinging is the only possible technical way to find out about updates to a site. Google and other search engines seem to do pretty well in keeping their indexes current, even though they don't receive any pings. And they're indexing billions of web sites, while there are only tens of millions of weblogs.
So when our tools all ping weblogs.com and blo.gs, why is it so crazy to assume that an update on a TypePad weblog, for example, would propagate as a ping around all interested listeners within 5 minutes? Or even 5 hours?
I had high hopes for FeedMesh, because I believed that ping federation would solve at least some of the problems that we see. But alas, I don't really see that effort going anywhere. 
So we decided to do something about it. For services like TypePad and LiveJournal, the issue of authentication & spam pings is not as problematic--if you connect directly to us, we can provide a stream of updates to blogs on our services that listeners can watch.
And starting today, that's what we plan to do. Read Brad's post to find out the technical details, but basically, you'll be able to make an HTTP request to http://updates.sixapart.com/atom-stream.xml, and have Atom updates from LiveJournal and TypePad streamed directly to your client. 
And if you're interested in consuming the stream, take a look at Tatsuhiko's post about his new XML::Atom::Stream module, which provides an event-based wrapper around the stream and integrates easily with XML::Atom.
In order to solve the real issue of spam blogs--particularly the huge number that are being produced by the same weblogging tools that you or I use--I believe we'll need to think about reputation built upon identity systems like OpenID. But in the meantime, we're happy to provide a valid source of pings from millions of weblogs powered by our tools, and we'll see where it goes from here.
 Yes, obviously, those updates are not without issues. Weblogs.com pings often time out, and requesting their changes.xml may not be that much more reliable.
 I even developed a CPAN module for receiving FeedMesh pings, back before I knew it was FeedMesh. Which is why it's called POE::Component::BlogCloud instead of Poe::Component::FeedMesh. But of course, I don't actually know if that cloud really was the FeedMesh, which may be the least-documented protocol ever. Yes, I realize I'm not really making a good case for FeedMesh.
 TypePad updates will start to be added to the stream tomorrow.