I have 2012 Prius+ with 180 000 trouble-free kilometers (112 000 miles). I haven't noticed any changes in battery behavior or mileage so far. Car life-time mileage is 5,5 l/100 km (42.7 MPG). There are quite a few Prius+ taxis around here too. I haven't heard of any problems with their batteries either.
Thanks for the update! Gives us hope that Toyota can still be counted on for reliability (even if the battery chemistry is different on the new Prius).
