PS4 will carry on leading IMO. X1 was already available with Kinect for less than a PS4 at one point in the UK but didn't really push the X1 massively ahead.
Definitely think MS have made the right choice in dumping the mandation of Kinect with an X1 purchase though. It'll at least give it a fighting chance. Rest of it will come down to what games come out on both systems in the next 6 months now.