To me, 0.x version numbers suggest that a project is not stable and can change in incompatible ways at any time... or be abandoned, even. 0.0.x, even more so. That said, some projects stay in 0.x territory for so long that this no longer applies.

0.0.0 is kind of weird... for some reason it suggests to me that zero lines of code have been written so far. (If there was code, the version number would have been higher.) But this is obviously not the case here. I do wonder what versions they used before this release?

Then again, I know of at least one non-trivial project that used negative version numbers... I guess, in the end, it just means what the developers say it means.