The difference is really noticeable.
Phone reaction time is much better.
Writing is more accurate and faster.
It remembers my last KB view(i prefer multi-tab when i search my contacts)
Better text selection.
Not so happy with the memory... it went from 45 to 28 just in 2 hours.
(after heavy emailing with attachments, mms-ing and some facebook).
I will wait and see will the mem go up .. or i will have to reset/bat.pull
For now .122 is a must have if you are running the old .78 !