I'm surprised this is being cast as Amazon responding to Google's price cuts- the AWS conference was scheduled months in advance so if anything Google heard about the price cuts and announced their own just ahead of the conference as a (successful; apparently) attempt to take the wind out of Amazon's announcement. Interesting that they dropped by the same amount; either it was a lucky guess, Amazon adjusted their adj…
Of course waiting to do a price cut till their competitor does leaves a bad taste in some customers' mouths. But I bet they think they're far enough ahead that it doesn't matter. Would Netflix and similar big AWS customers really leave AWS over something like this?
* This strategy even has a name: "follow the follower". Very common strategy in sailing.