But beyond filtering of people, there's many other social-augmentation things you could do - I'd quite like a face-recognition remind me of their name thing. Or people to annotate people with notes so I can say last time I bumped into them we were talking about X.
What will be the effect of knowing people's name only through your augmentation? Of a small number of people you see very often you'll learn their names (and you would have also without augmentation). But what about the large number of people in between acquaintance/friend and "have seen before"? Will we try less to get to know people as we have all the information about them we need for our purposes via augmentation? Don't we care less about people unless we see them very often? Will people become symbols of their information in our database only to activate the augmentation to recall that information?
I probably am too pessimistic (I call that realistic :-), but in the end, I wonder, do we control where our future is going with technology like this or do we wake up someday to a world we don't fit in anymore?
"3 people are looking for a fourth for tennis, 1.2 miles away".
As to the rest, there were identical dire warnings with the rise of cell phones. We seem to have managed.