[akkartik]

But you can mutate bigtable cells. Datomic seems dramatically different in that respect.

[Evbn]

Can you? Or do some apps just always ask for the latest timestamped version when they read?

[akkartik]

You could but it's not enforced. In practice, teams at google seem to use the time axis in myriad ways, and seldom like datomic.

Also, always reading the most recent timestamp doesn't use time like datomic does. You aren't querying by time and so on.