Just because they're part of the same code push that did something stupid, doesn't mean that they're bad too! Sadly LJ has failed to point out just why you might want to use them (along with the similar trackback).
Here's the Wikipedia entry on pingbacks.
(You can take my disapproving comments on the rest of the push as read, along with my "I'm not going to splurge out-of-context comments all over the social web" statement. I'd like to think you all know that I wouldn't be that stupid anyway!)