Last night on Late Night with Conan O'Brien, the guests were Lucy Liu, Jon Lovitz, and Michael Jackson (the beer guy). As is typical of these shows, the first guest is the biggest star, the second guest is, well, a secondary star, and the third guest (typically a comedian or band) is the one most likley to get bumped if one of the first two guest turns out to be more interesting than expected.
Conan did the "In the Year 2,000" bit (which gets even funnier the firther we get from 2000) with Jon Lovitz. Normally when he does this bit, his Year 2,000 partner is the primary guest for the evening. They do the bit, then cut to commercial, then go on with the interview.
Last night, however, they wanted to make sure no one thought the entertainment industry go there priorities confused. After the Year 2,000, they sent Jon Lovitz back to the green room, interviewed Lucy Liu, and then let Jon come back out for his interview.
They were both great interviews, though.