As I said in the other thread on the Marathon, I do believe they've made the right decision.
However, I honestly don't like the terminology "finally".
The storm took place Monday night, and even now I don't think they understand the total picture of the devastation, the ramifications, and what's its going to take to make the areas hit by the storm whole again.
In the cahos immediately following some decided it would be a good idea to help give NY a lift, by continuing with the scheduled marathon.
In the midst of that cahos they made the wrong decision. As they have seen more of the picture of what this crisis is going to call for, they've admitted their error, and cancelled.... which was the right decision.