It slowly unfolds over the first 7 minutes or so, intercut with the interview, but he drops the bombshell at around 5:35.

huh. how about that.

okay.

okay, new question. why is this a thing? i can't remember any point where andrew wk was presented anti-corporation. nearest i could tell he was about rock and party.

Well, when he was purely the "party hard" guy, there were rumors about this sorta thing... that Andrew WK was this whole manufactured entity.
Here, he's admitting to it, and apparently, it goes beyond what anyone thought (ie. the fact that there's more than one person playing Andrew WK).

So, in response to the response to this, he's arranged an open Q & A session that'll take place in Brooklyn in February. Should be good.

Hm, didn't mean to reply to you, but while I'm here...

I don't know whether I believe him or not... or even if I want to believe him or not, and I love that. I mean, either he's admitting to being disingenuous OR he's being disingenuous in admitting he's disingenuous. Whichever it is, he's playing with his audience's notions of his authenticity and how audiences gauge and respond to a performer's authenticity in general. I don't even know if that's what he's trying to do... but that's what I take from it.