I find the sombre mood among the Leave camp to be particularly alarming, if they thought they had no chance of winning, or had no idea what to do if they actually won - why were they campaigning in the first place?
Bizarre.
I think this is going to end up being overturned, one way or another. It doesn't look like anyone wants our withdrawal to move forward, or has the bottle to actually proceed with it...
Because:
Boris wanted Cameron out of the PM's job so he could get in - now he's realised that even if he can persuade the rest of the Tories that he's possibly going to be a good leader his career is going to be dead whatever he does (he'll either go down as the PM who refused to take us out, or as the one who did).
Farage - his career as an EU politician is dead (no more milking it for every penny as a "protest"), and he's probably going to find it hard to get voted into parliament here.
Gove - pretty much the same as boris, except that Gove was far less popular with the public than boris ever was.
I don't think most of the Leave politicians were really doing the campaigning in the expectation that they'd succeed, but for career reasons, they've not got any plan for how to proceed now and are having to admit that a lot of what they built their case on isn't going to be possible or were outright lies.
In some ways Cameron resigning and not issuing the official notice but leaving it to the next PM is possibly the smartest move he's ever made as a politician. It theoretically buys some time and ensures that the members of his party who were working on forcing him out/vying for his job by playing silly political games with one of the most important matters facing the country are not going to get the juicy reward they were hoping for.