I think there was a thinBasic wiki in the past, I think at wikiDot. It didn't last very long.
But!
As of today, I really fully support your idea - especially the idea of community driven documentation. It could represent platform which could be used to keep the docs growing and Eros would just copy the contents before new release to help file. I already did an list of "needs to be amended" at Google Docs for those interested.
Petr
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