Here is just a short list of the new features.
New Finish: Glock’s nDLC finish is tougher, more durable, and is on both the barrel and the slide.
New Barrel: Glock’s “Marksman” barrel feature new rifling for improved accuracy.
No Finger Grooves: Now your fingers go where they want to go… which is not necessarily where the finger grooves were.
Ambidextrous Slide Stop Lever: Makes it easy to release the slide whether you’re shooting right or left handed.
Flared Magwell: Subtle but effective in quick reloads.