I don't know if such a service already exists or not, but if not, here's an idea that some enterprising soul could devise for Blogistan. They could call it "ping.com". What it would be is simply this: a pinging service. Instead of bloggers having to manually ping all manner of different sites and services when they update, like weblogs.com and Technorati, a blogger would just send one ping to ping.com, which would then itself send out automated pings to every service of which that blogger is a member.
I know that Blogger can be set to automatically ping weblogs.com, but are there any such pinging services available? Because it's no good being a blogger unless you're pinging stuff. Or writing posts like this, just so one can use the word "ping" a lot.