Google Plus is built on its GMail base. Thus, they’re trying to actively market their email through these ’email intervention’ ads above. I got one (in my GMail, oddly enough) and I found it just annoying. Though, like any advertising, it will have some results. Even Spam and that Nigerian stuff works some of the time. What I didn’t realize was that Microsoft had fired a salvo back, via the Office 365 video below. Ironically, it’s hosted on YouTube, owned by Google.