Okaaay: It's been pointed out that i misrepresented myself in the post below.
The allegation being that i'm actually pretty oblivious and have failed in the past to recognize close family members, good friends etc. on the street even when they were yelling my name and waving at me.
And in addition, i once walked through two museum rooms holding the hand of some surprised, unknown guy, because i 'd blindly reached for and grabbed what i believed was the hand of my younger cousin, but was actually the hand of above specified guy. Mea Culpa.
[And sotto voce: i did say i notice good-looking people. :)]
Let the record show that my point re. not making said good lookers uncomfortable, stands.