“Having the president on” can mean different things. To the English it means something like “bamboozling the president” or “faking the president out.”
That is not at all what Glenn meant, tone, inflection, context, etc. kempster is correct, the manner in which Glenn says things, especially the side-note, and other spots, bits he's done in the past, it is likely he will use footage of 0bama to create an *interview* -- I only said I didn't know what he was planning earlier as he didn't give any more specific head's up than that.