Been there, done that. It wasn't hard to write small utilities with Node, but to put it as an complete framework and do all we need is a bit of an task. It took me 1 day to get started with Node, but 1 month to get an web app up and running.
Major hurdle was, as mentioned by many, the async nature. Even with all those libraries, it is still a nightmare. I am yet to figure it out, but hope I will do it one day, once I'm free!!!