Louis CK: INxP
Louis CK is an ENTP. Remember ENTPs can seem Introverted. His humor tends to rely on making up dark surreal situations(both his show and his stand up have this quality) which is an Ne tendency, he also loves breaking everyday situations into dark bits which is a Ti quality.
if that doesn't convince you check out his recent interview on Conan
http://teamcoco.com/video/louis-ck-interview-george-w-bush
Eh, sort of. Louis observes moments that exist and prods them and takes them to darker places, or looks at society around him and comments how he feels about them IMO. Patton Oswalt (who is an ENTP) is more prone to making up situations, people and ideas. His show makes up more (it has to by its very nature), but is still more often rooted in a sense of realism (one episode even largely mocks how unrealistic sitcoms usually are as he attempts to start a 90s sitcom and can't). It can venture off into surreal territory, but I don't know if I'd call that its default.
I don't see your point with the interview. I've seen that and several other interviews he's given, and he does the same thing consistently: as much of the interview as possible consists of prepared bits. That isn't a knock, it makes for funnier and more enjoyable interviews than most people give. But most of the questions are Conan setting him up for stories and bits. The NY question is general, but he hones in on the Bush story, which I can't imagine he tells off the top of his head. Between bits, he leans back and puts his hands in his laps. He withdraws. He's been doing bits for interviews for a while.
Have you heard his album "Hilarious"? Well, look at this interview that took place before that album came out:
http://www.youtube.com/watch?v=8r1CZTLk-Gk
If that's any indication, I'll bet one or more of those stories ends up on that album he plugs at the end.
That's a bit that later shows up on the album. He has very little real, unscripted banter and almost all prepared bits and stories. For a real ENTP comedian interview, watch an interview with someone like Ricky Gervais, who constantly riffs off the cuff with the interviewer.