I did the upgrade and didnt notice too much of a change as of yet. I did notice when you hit the volume rocker, you now have the option of having "Priority" or "None" when changing the volume which is new.
Also, my wife who didnt do the update to Lollipop the first time through, now has this update to Lollipop.
Not sure about anyone else, but BEFORE this update, my battery was not lasting very long.....Since this maintenance update, the battery has been awesome! I wonder if the phone knows its getting replaced my the M9 when it arrives at my house