In some cases, especially new projects (like a new OS), I think the pain of using an immature-and-powerful language is less than using a mature-and-weak one.
The core team has reserved the right to break backcompat without changing the major version if they find a serious problem in 1.x series. So I expect that it will be a while (at least a few years) before 2.0 is created.
No one knows, and I don't think there's been (a public) discussion about it by projects leads. The only guarantee is that 1.x will not break anything (according to some definition of "break").
There needs to be more experience with widespread use and multiple releases, to see how far that backcompat can be held. Perhaps after 10 releases, it should be a lot more clear whether or not a Rust 2.0 will be needed.
Why doubt the amount that can be received from Gratipay? What do you need to see to consider using it for PyPy funding? Would a promise of, say $500/week, be enough to make it worth a bother?
Better it be the team account, to avoid having donors try decide "who contributes how much"... let the team decide. Also, please offer it as an alternative to PayPal on the project website.
No need to wait. You can dive in right now without losing much later (I think changes between now and 1.0 aren't going to be that drastic). The guides are really good.
People would, on the surface, see a different beast, even though it remains 99% the same language. Not worth it.
With this argument, every release that adds a new keyword (for example) would have to be given a new name, since it will very likely break some code. Question that remains is how much must the changes be before the thing deserves a new name.
No one implied people are expected to compile every compiler they want to use on every system they want to use it. Point was it's not hard. Maybe link to a message where you detailed your troubles?
You would not notice because it's practically the same. All files have the same names (afaik) for example. They are compatible, and eglibc was like a drop-in replacement. I believe they share nearly all code.