That's good news about more Google services.
That said and knowing this question was about Google services specifically, I'd like also say that with Wolfram Language out there to be a general purpose type language, developers would be well served to have OAuth and OAuth2 support in a more generalized way that developers like myself can use to call any and all services that we want to use without having to wait for you all to decide to support that service. While I can see OAuth code is in the HttpClient code, it is not publicly documented. I want to push hard for that to be available as a public option so that I can write code to call any service that uses OAuth and OAuth2.