Syncpad has an interesting experience building a simple node.js server and then rewriting that server in Erlang
Roder over at SyncPad built his app with node.js and then, due to performance problems, rewrote it in Erlang. He does a good job of not taking any shots at node while explaining his experience with each platform. In his own words:
Erlang was also a delight to code. It is a very rich language with lots of features and OTP is a great framework with which to build servers. The SyncPad server acts as messaging server, so Erlang was what fit best. I would encourage you to try your next project in Erlang as well.