I had two boys, then a girl. I said I would never go overboard with pink and ruffles! But, to be honest, I was excited for a little pink! :) I kept everything as far as equipment. The car seat was navy blue with stars- didn't feel the need for a more neutral or pink change, there. You will get cute girl clothes, I'm sure, but everything else will be fine to keep. I used the boys' blue jammies, etc for my daughter. Like others have said, she doesn't know the difference. As far as toys, I didn't change that up, much, either. Rattles are rattles and blocks are blocks. My daughter was a tomboy, so we didn't really do much for dolls and girl toys, anyway. Wait until she's older to spen any money on that stuff. Yours could end up a tomboy, too. (Just to elaborate- my daughter DID have some of the doll stuff, given to her on birthdays by friends, etc. but never took to it. So, she was given the opportunity to like them, but didn't).
Good luck and congratulations!!