This is sold as something for big sites: "70% of WP sites in Alexa Top 1 Million" but I promise you there is no conceivable way the amount of changes we make in our WP DB could not be handled in Git.
Thanks for your comment!
The only time you'd want to tie your data with your code is when the schema of your data changes. Existing frameworks like Rails use code-based migrations for this purpose, so you know at any point in your git history what the database schema should look like (if not how to migrate/revert your data to match that schema).
[1] https://github.com/apenwarr/bup [2] http://git-annex.branchable.com/ [3] http://caca.zoy.org/wiki/git-bigfiles
If you want to do something that makes no sense, asking for money to do it doesn't make it more realistic.
I'll prepare a blog post on how VersionPress attacks the versioning problem technically.
To make it tractable to do so with small, frequent, incremental changes to a DB, you'd need to be smart about tracking which scripts need to change rather than running a process to reduce the whole DB to scripts each commit.