I'm just finishing up two client sites that include blogging functionality.
Each time a new post is created or modified, the blogging software attempts to send a ping to rpc.pingomatic.com and rpc.technorati.com - this takes up to a minute to complete. Actually, I think the requests are just timing out and fail silently.
Since I can't find any relevant documentation on either of the two sites, I have disabled that functionality. As a result, the blog post updates have now become instantaneous.
Am I right in thinking that the whole ordeal of pinging servers with new posts has become obsolete?
Yes it's still useful. (if getting things indexed quickly is useful) Looks like the technorati address isn't the full address. And if we're talking WordPress, pingomatic is the default on all WordPress installs - and many folks never update this... and as such it's busy. Either of those things could cause delays.