We have been using node.js in production since almost the very beginning.

We have since switched to io.js and I would seriously hesitate to use node.js, due to the seismic gap release pattern, which is actually more likely to create issues. Node.js is definitely not "more stable" as Joyent like to claim.

io.js has almost all of the core developers from the original node.js, which is now basically just a ghost town.

For stability, critical fixes and core developer support go with io.js.

Not to mention, that breaking your services apart (to some extent) becomes pretty easy to test, and with something like docker/lxc it becomes trivial to test/configure a new service with updates for deployment in isolation from the rest of the system... and tested independently.