While I haven’t been able to duplicate the problem here in DC at the convention center, there was a Twitter outage today as the site migrates to HTTPS: for heightened security. This move is especially important as it protects users from eavesdropping on unsecured wireless connections – typically a WiFi AP with no encryption like you might use at Starbucks or McDonalds.
The company is aware of the problem and TMCnet sister site Techzone360 has more.