Here's how I see importance of this new concept as to how it pertains to the upcoming production version due in 2018 and to Subaru's near-term future, and in this order:
1: It announces to the world that Subaru will re-enter the 3-row market. Those who follow Subaru closely already knew this, but the rest of the world didn't.
2: It will be large, very LARGE. The only specs given were the dimensions. Nothing was said about the powertrain.
3: The styling will be conservative and follow the current Subaru design language.
4: This will be the "anti-Tribeca." Every criticism of the old Tribeca has been addressed and rectified.
5: This showcases the flexibility of their new global platform. The Impreza is at the small end, and this 3-row shows how large it can be.
6: It also gives Subaru a vehicle to spin off other products, should they decide to. How about a right-sized pickup, like Honda did with the Pilot which begat the Ridgeline? Or maybe even get into the mid-size commercial van market, to compete with the Mercedes-Benz Metris? Both could be developed as variants of this SUV without too much difficulty.
While this concept answers a lot of questions, it also raises many more.
While the Tribeca was too small, will this new 3-row be too large? I don't think so, but releasing this concept so far in advance of the production model gives everyone plenty of time to get used to the idea of a large Subaru.
The other big question is the drivetrain. There have been rumors of a 2.4L DIT, with possibly a 3.6L H6 option. My guess is, if they offer an H6 it won't be based on the current H6. That's an old engine with roots that date back to the original 2.7 found in the ancient XT from decades back. It's not very efficient, at least when compared to modern engines. My guess is they will either add 2 more cylinders to either the Forester XT/WRX engine, or the rumored 2.4 DIT, resulting in either a 3.0 DIT or a (all-new) 3.6 DIT.
Will Subaru be able to engineer a CVT to handle much more powerful engines? It's possible to do so as the large powerful Lexus LS hybrid had a CVT. Also, there are some very large and powerful agricultural vehicles with CVTs. Or will Subaru develop a dual-clutch transmission (which could also be used in a future WRX and STI)? Or will they just offer a 8-speed (or more) conventional torque converter transmission, like other automakers?