This is... nothing like supporting IE6, and furthermore your opinion of IE6 sounds like you really don't get the point of supporting it to begin with.

While I'm not an IE6 advocate, support for that browser generally comes down to the general percentage of it visiting your site. If there is convertable revenue there you will (99% of the time) end up supporting it; if not, that's your loss. This is a hard fact.

The same thing goes for Node. There are countless numbers of programmers operating on a Windows stack; the large number of Windows machines opens up Node to an adoption level that's actually far beyond what it could ever really gain with just Mac/Linux/BSD alone. It's possible Joyent has a vested interest in this, but I'd also wager it's just about being available to as many programmers as possible because the market is there.

there are major costs to support legacy and incompatible plattforms, costs mostly paid in additional workload and testing, loss of "agility" and speed. it's very impressive how far node.js has come in a very short time. yeah maybe the raise in market-share (and additional developers for the ecosystem) will be more valuable than the costs, maybe not.

i, as an egoistical dev-on-mac, would rather see a stable 1.0 for mac/unix soon, than a 0.8 for max/unix/win within the same timeframe.

as a thought experiment: would native max os x apps be as sophisticated as they are now, if all devs had decided to port them to windows (xp / vista / 7 / ...), too.

Anyone opposed to supporting windows can go on their merry way using linux/osx. Don't forget the potential for creation of new modules (and possibly the evolution of nodejs itself) from the massive legion of windows developers out there.

Doesn't sound like a humble opinion. I would also like to know specifically why. What are they trying to achieve with it? Without it you have inane platform wars on the sidelines. The context changes a lot with that little piece of info.