when i was pregnant the first time round back in 1991 it was almost unheard of to tell you what sex the baby was, so it wasnt an issue. I got pregnant again in 2003 and it was always the first question anyone asked, did i know what sex it was. I had no desire to know because to me, it is all part of the joy of giving birth. I know i always feel disappointed if i dont get to ask "what did you have?" I already know.
I think these days we know too much. So you can decorate the nursery, big deal. If you really wanted to go with pink or blue then there is plenty of time after the baby arrives seeing as most people dont even use the nursery until the baby is around 6 months old. This is entirely a personal thing though and if you need to find out for whatever reason then thats fine too but from a personal point of view, yes, i love that element of surprise!
Good question!