There's been a lot of debate surrounding Stoudemire and whether or not he's actually of much value to this team anymore, at least as far as him in the starting lineup goes, but there's no denying Iman Shumpert's impact on the Knicks.
With him out, New York is playing an ultra-small lineup that features Jason Kidd and Raymond Felton starting in the backcourt. It's worked for them so far, but when they meet a team with a good shooting guard they have to rely too heavily on Tyson Chandler.
Shumpert makes this team so much more than what they are right now, and currently they're a pretty darn good team.
The Knicks will most likely be without him for a while, as their hot start and the severity of his injury means it would make more sense to let him take his time returning to action. Better safe than sorry.
It's going to be at least until January before Shumpert can come back from the torn ACL that took him out in May of last year, but his return will send shock waves through the Knicks organization, especially if he can come back and play at his former level.