The SMF Vent has been spiked a couple of times in the past week by junior high douchebags, so in response SMF thought it would work to cloak the vent from people being able to see who was online. In turn, it breaks the vent widget. We need to see if they will uncloak the vent server ASAP, as it's not a deterrent for vent spiking at all. People can still go to the Ventrilo.com SMF Alliance Vent Status Page and see how many people are online.
For now, we'll all just have to blindly log on without knowing who is online. Sucks, I know, but that shouldn't be a deterrent for getting on vent by any means.