I think it may be useful for the lock screen. Wouldn't it be helpful to see a Gmail-style snippet of your new emails visible when you unlock your phone? Or possibly a small calendar display so you can see at a glance that there's a meeting you're booked into later? I guess it might be difficult to integrate these things without dramatically reducing the space visible for apps but I can imagine a lot of people having a use for this kind of functionality and Apple is denying people the choice at the moment.
