Is Google App Engine an example of serverless? The user does not really think about servers, and the code is mostly written as event handlers. The abstraction is a bit leaky though, and you can tell that there are instances being spun up and down.
Depends on what you mean by serverless I guess. GAE (and Heroku for that matter) still has the notion of code running on an instance, dyno, server whatever. When I think of serverless, I think of Azure Functions, AWS Lambda and the like, where the cloud runs a single function in response to a request. How is it run? Doesn't matter, you pay for what you use.
FaaS (functions as a serivce) and App Engine are not the same thing. They're both a platform as a service (PaaS), but that's where the similarities end.
The difference is that traditional PaaS like App Engine and Heroku imply a certain amount of lock-in (although this has gotten better over time), whereas Serverless is a more raw compute service that is no more locked-in than, say, EC2.
Google promotes Services on Google App Engine to be used in a microservice fashion. If you create a new project and click on Services, they include a link to the docs about microservices. So if we go by that, it seems to be more microservices than serverless. Based off the article, the serverless (FaaS) bit would be Google Cloud Functions.
Terms such as "serverless" don't have a fixed sharp-edged meaning but are very fuzzy categories, except on a per-person basis, where you may (will) find people insisting on a specific meaning. When this story was submitted on some reddit forum (forgot which one) everybody was up in arms after just reading the headline, screaming "everything is a server" and "there is no cloud"! Don't take it too seriously. Human language is very deliberately a very flexible tool, with the same word fitting into very different contexts, taking on very different roles. Even in science, by the way.
