Mine has a bit of a downward curve, and even when fully hard, as in good morning wood, or else a very impressed, very sincere "you're so hard" from the girlfriend, the head still does point down, and the base of the shaft is no more than 90 degrees from down.
Still, although I too used to worry and be embarrassed about the curve, I have found it to "hit the right spot" every time. My cock is perfectly symmetrical in the East-West direction, and it easily slides past the cervix in as comfortable a manner as possible.
"I love how it curves" is one of the greatest compliments ever, to a guy who used to be afraid to unveil his cock because it wasn't up to the aesthetic standards of porn (and real life), where it more often than not points up, and if there's a curve, that's up as well.
I'm happy to have a cock that hits that spot, more often than not. | 
