Everyone had responses that were helpful. Let me state that we have had talks with her about her "giftedness" - thus, the book that I bought her so that word "gifted" could get fleshed out a bit. The woman who did the testing talked to DD about her results. I have talked to DD about her her "fast brain". I didn't feel like I was withholding information; I just wasn't keen about mentioning a number. I had read quite a few people mention here that that wasn't a good idea. I really like the ideas of showing her the bell curve as she is very visual. I will see if that satisfies her curiosity.
Let me state that DD is very convinced that she is not as smart as her sister(who is one of those MG kids who is a leader and super organized). We are really working on DD's self-esteem issues. I am trying to figure out how doing more explanation could help her see herself in a better light. This is very tricky for us - we have just started navigating the gifted world, and we are not very sure of what we are doing.
I hope that we really don't come across as not being honest with her - perhaps just not knowing how to handle this very new information about DD?