Qt 5.3 introduces high-precision touchpad scrolling using XInput2 on X11. This breaks QtQuick's ScrollView and Flickable, however.
Run the following on X11 using 5.3 Beta
and then on a notebook do a little bit longer flick. You can also wrap a QtQuick Controls ScrollView around the ListView. It will flick from index 0 to around 200 which is way too much. Even with a ScrollView which doesn't really have momentum, it scrolls to around 50. This works with a traditional Qt widget based applications where the scrolling is precise (does not scroll in deletage-heights but pixel-wise) and stops when lifting off the finger.
It seems as if the Flickable/ScrollView got the high-precision scroll events (ie. scroll 100 pixels) but interpreted them as mousewheel scroll 3 items per event (resulting in a 300 item scroll)