About the huge cost increase people mention in the comments: New cost unit is IH (Instance Hour) and GAE python scheduler has a habit of revving up new instances aggressively. To lower costs one needs to lower Max Idle Instances and -maybe depending on the situation- increase Min Pending Latency, thus lowering the Instance count (and the cost).

With the price increase and very harsh cut down on API free-quotas (plus the absence of long expected SSL on custom domains) GAE no longer seems a good option for me :/