I'd think that using back-end instance(s) to off-load the computational intensive work on GAE is pretty much the same thing as switching to EC2. I'm guessing t

I'd think that using back-end instance(s) to off-load the computational intensive work on GAE is pretty much the same thing as switching to EC2. I'm guessing that Google Compute Engine wasn't generally available at the time of the decision, but you'd be able to solve most of the issues described with a well thought out front/back-end GAE/GCE architecture since GCE is formally launched now.