I think this is a good idea also and like some of the other members here, I think it is still a little rough. What I have so far found:

1) Notifications (e.g., missed call, SMS, etc) do not appear on the standby screen anymore

2) The behaviour for notifications on the lock screen has also changed, instead of swiping to go to the application, you've to tap and you can take various actions from there, e.g., for a SMS you can reply, delete, etc.

This indicates that a whole slew of new phone interactions can be introduced which would be good for the N9.