You're confused because Kevin (no offense to him) doesn't really know what he is talking about. Nirvana has nothing to do with "becoming one with the universe" and "literally obliterating one's consciousness" is a really bad translation of the doctrine of anatman. It isn't a metaphor, it is a genuine metaphysical and prescriptive doctrine.

He is right that Buddhism should be part of the conversation. The damage New Age, Depak Chopra bullshit has done to the West's image of Buddhism is really a shame, though.

It just sounds blatantly self-contradictory

:D We're talking about religious metaphors; are you surprised? I think the heaven metaphor is also self-contradictory because I don't think the idea that Christian heaven = absolute, total, eternal, maximum pleasure is accepted by most theologians.

http://www.ted.com/talks/jill_bolte_taylor_s_powerful_stroke_of_insight.html Jill Bolte Taylor talks about one thing that I think would go into a real physical equivalent of Buddhist Nirvana, an ability to dissolve the barrier your mind creates between the atoms that make up your body and the atoms that make up everything else around you.