UPDATE #2: Twitter.com is down again although TweetDeck and other Twitter clients seem to still be working this time around.
UPDATE: After about 50 minutes of downtime everything seems to be back and running again.
At about 3 a.m. EST Twitter went down and has yet to come back up. Considering the fact that this obviously isn’t a peak traffic time, it’s possible that they’re under some sort of DDoS attack. This is pure speculation and I have nothing to back it up with but the timing of the outage does seem a bit odd.
I have an email in to Twitter support to see if they have a comment on what exactly is happening.
Ironically on Twitter’s status blog there are currently 20 retweets on the fact that Twitter is down so it seems at least 20 people have somehow managed to squeak in a update.