Not at all. This is still wide open. I happen to like generalized thunks because they remind me of Ruby blocks. But I realize there are more ways to skin this cat. Keep it coming!
question, do you want thunks to be able to take arguments? is being able to write something like this a target?
iterate(list): (x): print x
Since we already have a for loop, I'm not sure what the use case would be, but it might be nice, yes. Feel free to call YAGNI on it until a better use case is found. But I imagine it would be easy enough to add on later in the design -- thunks can have free variables anyway, so providing a way to bind some of those ahead of time (and designate them as bindable) should be easy.
--Guido van Rossum (home page: http://www.python.org/~guido/)