I didn't realize it was coming out yesterday, but I picked it up on the way home from work for 360. I think this version has a lot of physics improvements and the skating has really improved since last year. NHL 13 everyone skated like Dan Cleary, it was annoying and almost too realistic in that regard.
When I started the game up it went through the normal settings: whats your favorite team, etc. However, it also had different 'modes' I guess you could call them. The options were High Impact, Simulation, and Hardcore Simulation. If I understand these correctly, they alter the way the game is played. High Impact focuses more on hits and arcade style games while sim and hardcore sim make it more like a simulator and realistic. I chose hardcore sim.
I actually really like the way this version of the game so far. I've only been buying them consistently for the last 6 years or so, and they usually add a thing or two: board battles, improved faceoffs, etc. This year the game seems more refined than any of the previous I have played.
One thing to keep in mind, it actually makes more sense to develop a core engine and add to that every year fixing 'glitches' (which half of the time are high probability shots) so that way you are constantly improving on that engine. If they start from the ground up, it will take 5-6 years for the game to be as refined as it is today. No matter how you slice it, starting over is starting over. It's like buying a first year car, it's bounds to have some quirks.