+1, what about performance? Does this mean all server will be blocked while doing IO?

No, it says one thread per request, not single-threaded.

sorry. missed that one. Again, I believe multi-threading is not best approach in terms of scalability. Asynchronous io is the secret sauce of node and it distinguishes node from other server side technologies. I think, asynchronous nature doesn't suite well to meteor's approach. I will be appreciated to learn real reason.

I thought they were using fibers (https://github.com/laverdet/node-fibers) so much more scalable than threads but slightly worse performance than callbacks