I've been messing with node.js for about two years now. It's a beautiful system. Most people don't get it, but that's fine. The bigger problem had been there was no-where to run your code, if you didn't maintain your own servers.
And who seriously wants to do that, if you're not getting paid for it? It's a time sink.
I've been waiting for a major provider like Dreamhost to enable node.js. A couple of small providers have started up, but it's kind of a premium service. And that's a shame, because the first job of node.js is not to take over completely from your old site, but initially to "plug a few gaps" in the big internet puzzle - mostly all this crazy new 'real time' websockets and messaging stuff.
...like a chat client. Everyone loves a little chat client. But you're not going to redevelop your entire site and chuck Apache, with all the pain that would cause, to get one. You want a cheap little 'experimental' side-server that fills that gap, so cheap you essentially forget about it.
Well, along comes RedHat with their cloud computing platform called "OpenShift". I think they changed it recently, because I remember it having a much more sensible name and a lot less features the last time I checked.
I'll skip over explaining their funky new words for everything (like "cartridge", clearly intended to harken back to your halcyon Nintendo days) and just say that, FOR FREE, you can have THREE servers spun up for you, pre-loaded with all kinds of linux-based server setups such as Apache, PHP, JBOSS, or node.js.
If you're used to FTPing into your hosting server, then OpenShift is going to be a shock, due to the heavy use of GIT to transfer files. It seems crazy at first, especially setting up the SSH access keys if you don't have a unix box handy, but there is a method to the madness which becomes apparent when you start to 'scale'. Using GIT to deploy files to one server seems completely excessive - although it does do some cool 'merging' of your code with the latest server upgrades - but the moment you need to deploy to half a dozen instances, you'll see there's no better way.
All other providers I've tried work in a similar way. If anything, RedHat has streamlined the process to it's simplest. But why does the typical node.js deployment system 'force' you into being scaleable? Because if you don't start out that way, you never will.
Yes, socket.io and websockets work, I've tested it. (You have to be aware it appears on port 8000 externally, regardless of what you thought it would be. And only the websocket connection method works - no comet fallback that I know of.)
Widespread use of node.js and websockets is likely to reduce global internet traffic, by removing all the inefficient ajax 'polling' or comet 'long poll' IP connections being made and remade, a billion times a minute. node.js can handle more users and page hits than PHP. But none of that mattered while we didn't have any damn servers to run the code on.
So, Thanks RedHat! You've made my day, and solved one of my longest-standing network plumbing problems, for free. And you've made the internet better. Thank you.