It is faster to rewrite an app having written it once already, but still: it took half the time, had better user login/auth, and had sort-of real time multi-user support.
Meteor is very nice. Try it on a small project. The learning curve is easy.
People that don't or haven't tried to understand node.js or express like meteor. Picking up meteor is easier, but its not all that useful at the moment. There are other frameworks that are better than meteor and allow you to achieve the same end (realtime).
Don't get me wrong, it is neat, and I am glad they are exploring a new area of development, but promoting it as anything other than a pet project is misleading.
Meteor is for writing highly interactive/reactive applications and I don't know if it is even meant for massive scaling.
There is a sweet spot for Meteor for apps that will not have millions of users.