Well, I don't see any sign of it in my settings: I looked in the desktop settings as well as in many of the system settings dialogues. I didn't actually use a mouse with a wheel at home until recently, but neither my home nor work desktops suffer from this, so either Kubuntu and Red Hat switched this off or it just wasn't there to begin with, especially since in the former case I had no reason to even switch it off until recently after I first knew of the feature from KDE 4, so it should be enabled by default and exhibit the effect, but that just isn't the case. Maybe I was "in the zone" and in a fit of rage sought it out and hit the switch, but I'm doubting that right now.
I appreciate that people don't like change, which is probably how my remarks are interpreted, but sometimes one has to eliminate disastrously bad features just to avoid the need to have someone hovering behind new users helping them turn all the bad stuff off. And 3.5 still rules, by the way. ;-)