Now we know what Twitter's good for: not muchSo my boss is at Macworld right now and he's expecting Twitter's Jack Dorsey to take the stage in a matter of minutes. Of course, you should be hearing about this from him in our liveblog of the event. But we used a Twitter embed. And it's broken. And, depending on when you're visiting the 'Wag, it's either not working or loading really slow. Break a leg, Jack!