As promised Google went on an data store overhaul today.
One good thing is that there was no significant application disruption during the maintenance period, except of a short
write-only read-only period that was pre announced by App Engine team.
Second good thing is that judging by my appls average response time the results are excellent.
This is also depicted in Datastore Status Page, which for historical reasons I am attaching here.
From the picture we can see that after around 03:30 PM when maintenance finished datastore latency dropped dramatically, also we do not see any spikes (well not until the time I write this - fingers crossed).
So lets keep the picture here and see how today's maintenance will affect App Engine on the long run.
Meanwhile I can see a change in Python's average response time which seems a little elevated but more steady than before.
Kudos to the App Engine team for the work they have done during the weekend to minimize potential problems.