I can't say I'm surprised by this, to be honest...if it was going to come out in 2015 we would have had a release date long before now; the signs were there, it just needed confirmation. It's always better to have a good delayed game than an earlier released bad one, but it'd be nice if developers were a little more upfront, honest, and realistic about how long it's going to take them. Summer 2016 for Japan, Winter 2016 for America, Q2/Q3 2017 for EU. Region locked to prevent importing. Plus the Atlus tax. I wouldn't put it past Atlus to do that. They love treating Persona fans with care and respect, just like Square Enix treat their FF fans, Nintendo treat their Pokemon fans, and so on and so forth.
I wasn't going to buy it either way, because I just don't care for the series, but still...keeping promises doesn't seem to be the thing to do in the industry these days, even in Japan, so it's disappointing to see on some levels even to me. It's getting to the point that you can't believe a game is going to be released on a certain date until you have a copy of it in your hands.