Originally Posted by
canadiancow
That page says you can use the card in the kiosk. It doesn't say you don't need to carry a valid passport.
Nevertheless you don't when flying US-Canada, be it in Canada or the US (preclearance or not). And except for Canadians at US airports, yes, the card works in GE kiosks.
I now called the CBP at SFO, ORD and EWR to ask if Canadians can use NEXUS cards in APC (rather than GE). They said you can't, and should go in the "special assistance" lane. SFO and EWR said the blue customs form is needed in that case, but ORD said it isn't.