What are the implications of node.js?

I think the major implications are two-fold: huge performance and scalability gains, and the possibility of creating web applications where two or more people may work on the same web application at the same time, watching what the others are doing, in real-time. This latter one not only has big implications for web-based gaming, but also collaboration tools, etc.

It would appear that node.js is exactly what the real-time web needs. For that kind of thing, be sure to also checkout Socket.IO, which achieves cross-browser HTML5 web sockets. Combined with node.js, this makes for an incredible platform.

Check out what was made at the node.js knockout for some examples of what can be done.

I think what you can hope for is going to be more like twisted for Python, rather than e.g. rails for Ruby -- a rich, powerful framework, but still one requiring skill and care to use properly, because asynchronous programming is always like that... it's the price you pay for its absolutely awesome performance potential.

There are and have been Javascript server-side frameworks, but with server-side Javascript never being a really popular option, such frameworks never got the "critical mass" of support and enthusiasm that, say, jQuery has, or rails for ruby on the server side of things.

I doubt async programming (with its subtleness and difficulty) will be the defining trigger for a "mass movement" (hey, I hope I'm wrong, but I see e.g. the relative popularity for Python of Django, with none of the awesome performance, compared with Twisted, with _all_ the awesome performance... but the intrinsic difficulty too!-).

OTOH other developments (such as, simply, the wide availability of powerful, high performing, solid Javascript engines like V8) are more likely to eventually result in wide availability of (non-async;-) server-side Javascript choices, and as a consequence the possibility of the development (or porting -- e.g., a framework like dojo could already offer a lot to a JS server-side app, only parts of it are actually client-side) of powerful, simple, and therefore eventually popular framework. Nevertheless, I wouldn't hold my breath waiting for that either...

Node.js is an application server, not yet another webapp server. As the article says, it saves you the trouble of writing the event loop and using two languages to write apps (python/java/ruby/php backend, js frontend). As it is based in the V8 Engine by Google it's really fast and has a low memory footprint.

There's a web service framework called GeddyJS, and Node.js comes with a set of libraries for IO, database and math. It's also possible to extend it with addons, though last time I checked documentation was still a little rough on that.