I just wanted to add that it's good to have these doubts because it makes you really think the process through and gives you time to consider what it means to your child....the fact that you care I think is a sign that you will care to help your child(ren) in the ways that you can to be connected to his/her heritage.
My dh and I were very open to race, but when we were matched we had a moment of panic as to whether this was the right thing for her. We knew it was right for us, but we were concerned that we would do her a disservice by adopting out of race. So we do what we can to be inclusive, we seek out situtions for exposure, books and toys that are reflective of her heritage, celebrate cultural holidays, and educate ourselves. I"ll tell you we had the most pitiful Kwanzaa, but I'm sure we'll get better each year
First and foremost we love and adore our daughter (okay, we love both of them), part of having children of different races is honoring that which makes them special and different.