I did a couple of appearances on MSNBC Saturday morning -- I was meant to do three, but the car they sent for me (I love saying that) was late. The subject was Friday's release of the iPhone 3G, which required me getting an iPhone 3G, which took more than six hours and which I chronicled on Twitter . The talking head thing was all new to me, but the experience is not unfamiliar to the smallish crowd of local regulars: you are well dressed only from the waist up (one woman actually wore shorts) and you sit in the green room chatting amiably with each other, including your on-air adversary if you have one. Every once in a while somebody comes in and says, "You're up" and you are led to a sound-proof room with a chair and a table and a light in your face (think: film noir police station interrogations). There is a camera pointed at your face, you are told by the control room the name of the person whom you will greet in the next few seconds as if you are old buds and th