I think you guys are forgetting to mention one key advantage with using NME over flash. That is Haxe language itself, for obvious reasons.
"the secret thing is that it doesn't even have even remotely the same performance profile"
@Raoul Duke I would like to see this statement backed up I have not seen such a performance issue that would deserve that statement?
All in all I wouldn't recommend NME, HaxeFlixel or whatever for every type of game or every type of developer.
JLM is wise in saying "you will switch depending on specific factors".
Going back to Haxeflixel the current features and the api (although heavily opinionated) are often found to be very appealing to make most kinds of 2d games quickly and easily. The endless as3 games made with flixel proove this.
Now thanks to nme they get the wonderful drawtiles implementation for cpp which is much more appealing than the Adobe Air alternative.