Technical/spicy take:
I've always had a theory that SE's servers run on rather outdated hardware and solving performance issues/migrating to newer architecture etc is problematic (Eg: look at how long EU servers had horrible rubber banding in duties for back in SB).
If that is indeed correct, running the servers in the cloud (Aka basically running on AWS or Azure etc) will give SE far more flexibility to scale the capabilities of the DC up or down as required and most importantly, they should be able to scale it virtually overnight.
As long as the entry point isn't problematic, aka ping, I think it's a neat idea and I'm glad to see them try it.