6. Read Up on Reviews: I cannot stress this enough, you will avoid disappointment and having to return items that don't live up to expectations. Since you can't exactly open every package and try things at the store, consider reading online reviews (I went crazy and did this for nearly every item). Sites like epinions, buzzilions, and viewpoints can be helpful with this. If you are registered at a large store like Babies R Us, you have the convenience of reading the reviews online by other moms and dads and you can add and delete items in your registry as you find out what will work best for you. You can of course ask other moms you know for advice in person, but I think having 20 opinions beats two or three, you get a much broader perspective and more accurate conclusions about products.
7. Try Alternative Registries: If you know that most of your guests are online and are computer savvy, consider online registries. There is a lot more options and flexibility registering with amazon.com or myregistry.com than in a brick and mortar store. This way you can add nearly anything you find on the internet to your registry and are not restricted to store inventory. Your guests can also get the best deals and prices and often free shipping. Consider having one of these as a second registry with a few items that are simply not sold in stores but you really want to get.
Finally, if you have some time on your hands, you can always make your own breastfeeding covers, newborn booties, and pouch or adjustable ring slings. They are easy, fun, and very useful (not to mention a lot cheaper than buying), and you'll be proud to have something that is not store bought!