Not to disparage the 100:10:1 method, but I do disapprove of this implication. I don't want people to refrain from putting things out there, just because they don't want to feel obligated to support them.
I have a public blog, where I try to maintain quality, and a semi-private blog where I try to allow myself to post stuff I'm not sure about, stuff that's not interesting to anyone other than me, stuff I don't necessarily want associated with my public persona, and so on. I know others do similar things.
I think there's no particular mechanism to do that with open source, but it might be valuable. Perhaps I could have two github accounts, one where I'll put anything I feel like, and one where I put stuff I'm proud of and want to remain proud of. If something's on my "real" github, I'm saying that if you ask for support I'll try to help you, if you report a bug I'll try to fix it. If it's on, let's call it my shithub, there's no social contract. Take a look if you want, and feel free to report bugs, but I might just say "yeah, that's a bug". Or even just "not interested in that project any more, I'm not going to bother confirming this".
Then, if you want to follow this method and also want to make most of your code public, you can write down the 100, put the ten on your shithub, and publish one to your github.
 E.g. http://slatestarcodex.com/ versus http://slatestarscratchpad.tumblr.com/
"As Markdown's "parent", John has a few key responsibilities in shepherding his baby to maturity."
"And if you release, don't release more than you can realistically maintain."
"open source project leaders [...] have an on-going responsibility to make it easier for community members to contribute"
That is not what was being discussed, here.
"you should only release what you're willing to maintain"
The Markdown story was not about that. Nobody demanded John's involvement; all people wanted was for him to let the project go. That's a far cry from "willing to maintain."
Why should he have to do even that? It's his project to do with what he pleases. Work on it, horde it, release it under the AGPL... it's his, nobody else's. Of course, that's not their impression. Their impression, and the general expectation, is that if someone open sources code, they do so expressly for the good of the community of developers.
You see this quite a bit in GPL discussions as well.
I do think that if you're not shithubbing, you have a level of responsibility which perhaps Gruber and TJ (the maintainer in the second link) weren't taking. And it's not clear to me how much you can claim to be shithubbing if you have lots of users and are discussing the project direction and taking pull requests. (It looks like TJ has since handed over maintenance of n to someone else, which I'd say was the right decision.) The third link also seems to be talking mostly about projects which can't be described as shithubbing.
The main thing I want to get at, is that you should be able to put something online without having to take responsibility for it. (Perhaps we need to distinguish "online" from "released".) That doesn't mean you never have any responsibility.
 To be clear: I don't know much about these two incidents, but the actual details aren't particularly important right now. I'm discussing them to bounce intuitions off them, not to pass judgment on anyone.
Also, don't forget to update those notes if things change.
For instance, it's enormously helpful, in the aggregate, that people have repos that are simply "example of an application that uses Foo with a Bar adapter."
I will add as a side note, if you can't maintain something anymore, put a big heading on the README.md saying so. If it's popular, point people to a maintained fork.
(Nothing I write is extremely popular but I'm going to go through and "deprecate" a few things of mine tonight)
At least you'd get a hint at the intention behind the release.
I agree, anything I put out comes with one expectation on my part, I may be contacted regarding it. I do not feel any obligation to support it, I have no relationship with someone randomly contacting me over something.
Though, I put anything I want to be kept private is on bitbucket.
Have a just witnessed the moment of inception for a fantastic new word?
"Team, we've got to stop all this shithubbing and really start properly testing and documenting our code."
If you're reading this, chickenshit, I hope you make good use of that name.
But I think perhaps the core isn't just the license, but also the readme, and guidelines on naming/"trademark": eg: when it comes to markdown, the issue (as mentioned in a sibling comment) was more one of "I don't think what you want do do deserves to be called 'markdown' -- that named was coined for my vision of 'rich plain text'".
I'm generally in favour of strong copyleft licences, because of the need to maintain user (as opposed to, in addition to developer) freedom. But when it comes to stuff that's basically just some ideas that maybe someone else might want to run with -- I think it's important to give them away as unrestricted as possible. Technically trivial snippets of code aren't under copyright -- but with how hostile the "intellectual property" climate is -- I think it's important to be clear when sharing something unfinished that if someone else builds on it, one will not retain any ownership of/claim on the result (beyond what copyright law forces one to keep, hence CC0 etc).