last night over dinner.
This is an example of what I see via the web:
I can see both changes to schema, and do deltas between days (aka slice out a days worth of data or grab a snapshot of anyone one particular days data). The nice thing with hgweb is that I can make this happen via my browser :)
Part of what really makes this work is the --tab option to mysqldump (I also use Innodb so my backups are all done online). I can compress it, but frankly disk is cheap and storing deltas is cheap :)