Distinguishing between shorts and features
 

As in what particular criteria do you use to make the distinction and if there's some consensus to which we should adhere.

Personally, I've gravitated towards the Academy's rule that the 40-minute mark is what separates a short from a feature (the former being under, the latter being over), but I'm just wondering how widely-accepted that particular number is or if there's some conjecture on the matter.

Definitely hard to draw a hard line. Very much a "know it when I see it" thing. But the Academy line of 40 minutes is really good, I think. The more I think about it, the more that feels right. To actually answer your question, I think that feels right because anything shorter needs a condensed structure and anything longer can let its acts and developments "breathe" in a way similar (if a little tighter) to most multi-hour features. Less than 40 minutes, you get to the point where you need a fundamental restructuring to hit the same points in a natural way.