I just noticed on the PAX site that there's a new PAX Event going on.  Unfortunately no, it's not PAX Central like people have been asking for.  It's PAX Dev.  From their site:

PAX Dev, you say?
A few years ago, a group of developers asked us to host an offsite gathering while they were in town for PAX. That idea took hold, and from those conversations we decided to dedicate the two days before PAX Prime to the developer community. We're shooting for a small (750-ish), intimate setting where digital and pen/paper game developers alike can focus on their craft. No business. No press. Just sharing, learning and debate. Register today.

Interesting. It's nice to see PAX expanding in interesting ways. I wish all the PAX guys the best of luck; they seem cool.

Dev conventions always seem like a good thing.