If memory serves, Cory Doctorow commissioned flashbake, and he wanted it not for backup purposes but as the equivalent of old drafts of books and the like for scholarly research. Git in particular will commit with an empty commit message but is not thrilled about it, and I think there are other VCSes that are more anal about that, thus the need for some text was expressed and "whatever was going on for me while I wrote it" in particular was desired.

So yes, it is completely irrelevant for most purposes to you. I suppose it might be nice to run some sort of semantic analysis that notes that someone writes depressing drippy love poems when it's raining out or something, but I'll be damned if I can figure out why the hell that would be important for me at all. OTOH, flashbake also has a plugin that supports some crude notion of where the commit was written (pretty much gotten from the weather info), which might be more legitimately interesting.

Geotagged commits might actually be cool, especially on plane trips. Though I suspect most of mine would just be the latitude and longitude of my couch.

It strikes me that the other twitter/weather stuff is redundant in the face of the timestamps and geotags...

I could see that data being nice to review if you were writing a private diary/journal for your own future consumption.

Other than that, the concept seems pretty flawed - git is useful when you manually commit at the end of a chunk of writing, and again after an edit/change. Wrangling with commits made at preset intervals - when you're likely in the middle of a paragraph - seems like it would be a nightmare, and next to useless if you need to revert to an earlier draft.

But I want the future generations to know that I praised Justin Bieber's haircut on twitter while listening to his latest song!

Yeah, I agree - completely irrelevant. That time better get spent integrating diff-able formats like textile, markdown, even TeX into writers' versioned workflows.