I doubt we will see 260 HP in the new GTI. I'd expect a revision of the 2.0 TSI motor to find its way in, possibly with a valve lift system similar to Audi's, a better flowing head, and something to address carbon buildup. I'd expect around 230 claimed crank HP. Enough to keep it competitive.
I like their continued focus on reducing vehicle weight. That would only have good effects on the entire package. I will say, I'm a bit disappointed there are no reports of intent to use a 1.8T motor. Would save weight over the front of the vehicle which would also be a good thing, and help it get better fuel mileage.