Here Comes Facebook's Phone? Updates

It's time to see what Facebook is building. We've broken down all the speculation, and we'll be updating this post as information comes in, but despite all of Mark Zuckerberg's denials, it appears that some sort of Facebook mobile unveil may be imminent. Reporters are currently gathered at Facebook headquarters in Menlo Park, California, and AllThingsD's Mike Isaac just arrived at the event and sees a certain kind of reporter gaggle: 

Lots of phone-centric press in Facebook HQ lobby, along with intl. a natl. press. This is a mobile event for sure.

— Mike Isaac (@MikeIsaac) January 15, 2013

That doesn't necessarily mean a Facebook-branded phone, of course. But as we wrote earlier today, it could suggest an operating system. And Business Insider's Jim Edwards has new sources saying today's announcement centers on a mobile-ad product, which would be less exciting for the masses and more something for investors. The event starts in a just a few minutes, at which point we will get to see this exciting new... something that Facebook built.