Yeah, but...Daisey really isn't a journalist. He's a playwright and an author. He does one-man shows off Broadway. As far as I know, he's never had any training in journalism, nor has he worked as a reporter.

This is a case where I suspect that both parties were mis-interpreting the intent of the other party; This American Life does a lot of "artistic" work (e.g. nearly everything by David Sedaris, or David Rakoff), and perhaps Daisey felt that he fit into that model. Likewise, TAL seems to have felt that Daisey was venturing into journalism, even though he's clearly an amateur at it (they make skeptical statements to this effect in the original piece).

That said, I think there's a bright-line distinction between "art" and "fabrication" -- when you present your work as a documentary without disclosing it as a work of fiction -- that Daisey seems to have crossed.