[smacktoward]

Forking is always possible, but it was only practical because the community could plausibly claim to be able to put as much or more effort into building out their fork than Joyent could theirs.

Microsoft is a much, much, much bigger company than Joyent. If they decide they want to take things in their own direction, they can throw an awful lot of programmers at making that happen. Which would make standing up a fork that could plausibly claim to be at least as actively developed as Microsoft's would be much more difficult.

[dsp1234]

to take things in their own direction

And there is evidence that this is true. Node itself has had to make major changes to it's own code to account for unilateral V8 changes, and node really has had no choice but to suck it up and make corresponding changes. They could fork V8, but it's not likely since Google is always going to be able to throw more resources at it.

[ybx]

Forking isn't possible when the code is not there, and when the company that created/copyrighted the code is openly hostile to forks. By them releasing under MIT, this issue is resolved.

As for the manpower behind Microsoft, git has made it very easy to merge code from relatively similar source code - in the cases that they make large important changes, those can always be merged in, and usually without too much work involved.

The only way they could succeed with something like that would be for them to go closed-source again, in which case you're still better off than if they never went open in the first place because you still at least have some code to work from.