Hello Mr Acuity, I don't want to sound like one of those "Thanks for the update, now can you also add this and this for me?" buuuut.... One practical addition would is a way of separating notifications that we've replied to from those yet to be/and or a way of looking them up and/or by username as well.
Not only do some notifications get buried and aren't always as easy looking up (one mistake and have to start scrolling from the top again), those are often the juicier ones, the ones that require a lengthier and more detailed reply but got bumped by the growing plie of quickies on top.
So I hate to impose, but as you can see, it would be a most useful option.
Thanks for everything, this site is heads above the rest and then some.