Bringing out 2015 models seems ridiculous. I can see a couple months; but we are barely more than a couple months into 2014. So it's really a 2014 model, since come April next year they will have 2016's--meaning, the 2014 model will have been sold mostly during calendar year 2014. Perhaps that should be the definition: model year has to be whatever calendar year it was sold the most in. In which case, perhaps they aren't planning on refreshing for a longer time than usual?
In the end it's just another model number/name designator. So I don't really care. Although it's going to complicate things, as when you go to buy a 5 year old used 2015 model it's actually six years old not five, and ought to be cheaper as a result.