If you're not finding out the baby's gender, NotFindingOut.com offers a very cool service. Upon registration, you'll receive a confidential "Shhh!" card for your doctor's office to fill out and send back to NFO. Only they will know your baby's gender.
Once shower guests start shopping, they'll discover that everything on the site is paired in boy/girl complements, so the mom-to-be won't receive a sea of yellow and green, she'll just have to wait until the baby's born to get all of her gifts. In the meantime, NFO sends gender neutral "preview cards" of all gifts purchased in both their pink and blue variations. Once the baby's born, you call to confirm the gender, and a few days later, receive all of your actual gifts.