Man, there are so many choices for things like this these days. Meteor is kinda my go-to, but this does look pretty nifty. That said, I think I'm better of sticking with what I know while it's still in it's infancy than jumping from stack to stack.
Meteor is great, too. If you're looking for an integrated A/B testing module or 1st party PostgreSQL support, you should have a look at Node on Fire.