This is more a curiosity than a request (I prefer using my Gmail account to log into sites); is there a particular reason that users can't log into the Stack Exchange network with a Twitter account, or other OAuth services?
My initial thought was that SO only supported OpenID, but it has a Facebook Connect setup running, which means you have Google, Yahoo, and FB; seems like Twitter is an obvious missing piece here.
I wonder because I was considering trying to setup an OAuth/Twitter sign-in capability for my own site. What's the reasoning there?