Yes, the inertia/deceleration changed for me too. I was able to "reset" it by going into System Preferences and doing the following:
1) Go into Accessibility->Pointer Control->Track Pad Options and:
1.1) Changing "Scrolling" to "without inertia"
1.2) Scrolling Speed to a value that is one lower or higher.
1.3) Pressing OK
1.4) Exiting the Accessibility Options by pressing the "Show All" button at the top.
2) Going back into Accessibility->Pointer Control->Track Pad Options and:
2.1) Changing "Scrolling" to "with inertia"
2.2) Scrolling Speed to a value that it was previously
2.3) Pressing OK
2.4) Exiting the Accessibility Options by pressing the "Show All" button at the top.