Obviously it's meant to be ambiguous, but remember that the spinning top Cobb uses should not be considered his totem - it belonged to Mal. His 'real' totem is the wedding ring, which you need to follow during the film and it'll confirm what Cobb says - ''In my dreams, we're still married.'' Also, the spinning top never showed sings of wobbling if it was a dream (ex. when he puts it in the safe while in Limbo with Mal). And than there's that he sees his children's faces for the first time, etc. etc., although someone might say that it's the catharsis he went through while on this journey [through the dreamland], but personally, I disagree.
As for the waking up in the plane without the Pasiv Dream machine, when they're being hooked up, they're basically drugged, so we could go on explaining to ourselves that they showed signs of waking up, and were disconnected, while fully waking up later - but it doesn't change the fact that it's unclear and should probably be that way. That's why Cobb and Saito feel their wrists after waking up. Nice find though, haven't thought about that before.