I woke up to the dog stepping on my nuts. This is equally surprising, though much less painful. If GM is building a mid-engine car, and it looks like they might be, I really wonder if it will be the next Corvette for a few reasons. The current generation is still relatively new and while 2019 is a bit away, it seems a bit early for such a radical change. At the same time, mid-engine cars tend to be a bit more expensive, both to purchase as well as maintain and one of the key appeals of the Corvette is that for what it is, it's simple, cheap, and reliable. All three traits that make it appealing generation after generation.
That said, I can't imagine it being anything but a Corvette. Time and time again GM has treated the Corvette nameplate as top dog, even going as far as nixing cars that might compete with it. Additionally, if Toyota could make an affordable, reliable mid-engine car with the MR-2, I'm sure it wouldn't be too hard for GM to do so as well.
Edit: Also, I went to find Jack Baruth's editorial from earlier this year because he brings up the same talking points I've heard over and over for a few years now, just in a more persuasive voice than mine.