I still read to my two and DS1 is 8 (DS2 is 5). I fully intend to carry on until they throw me and the book out of their bedrooms in the evening.
I do know several people who don't read to their children at 8 though. It seems that as soon as the children can read for themselves the parents don't bother any more which I think is sad. You can read things together that the child may not even think of reading alone.
It is part of our routine, bath, joint story and drink (they have a book which we read to both of them) then off to their bedrooms and they get a book/chapter each in bed, I read to one and DH reads to the other. DS1 reads by himself afterwards, DS2 is asleep as soon as the lamp is off. Lovely.