NYSM is, at it's heart, a refreshingly simple film. Yes, it has twists and secrets and gambit pileups, but in a film about magicians robbing banks, that's exactly what it should have. What makes it simple is that it doesn't really have anything else. And I'm absolutely fine with that.
It doesn't overstay it's welcome, it doesn't fill time with a pointless romantic subplot (while there are actually two romantic "subplots" they're dealt with in such a minimal fashion that you could almost literally blink and miss them) or unnecessary action sequences (there is one action sequence in the entire film). It knows why it's here, and why you're watching, and gives you that, and only that. I've seen comments that the film seems empty or pointless, and, I guess, if you're used to a more hit-all-the-demographics approach then it might seem a bit sparse. I prefer to use the word "focused", but I can understand why that's not everyone's cup of tea.
Admitedly, this means the characterisation suffers a little - there's no real depth to any of the individuals, and you're given no good reason to really care about any of their fates or motives. If you want a film to get you emotionally invested, then this is likely not your film. If you just want to see come-uppences being got and banks being jobbed in a neat, stylish little package, then this most definitely is your film.