No offense Scott, but I think you're a little off base here. While everyone will I assume be pretty much wowwed when they go through the first time, that won't last forever. Also, people who are not HP uber-fans are not going to be as enthralled as the people who post here. And most important, there are going to be a lot of kids. A whole lot of 8-9-10 year old kids. This is fun. The line will be fun. They will be laughing giggling and pointing and discussing. As they should be, and I know I will. I don't think shushing would be the right thing to do. If someone doesn't like, understand or enjoy being around rambunctious kids this probably isn't going to be all that enjoyable.
I plan on taking my 7 year old nephew. He has muscular dystrophy, but he can still walk now. I guarantee he will be squealing in delight the whole time. I bet I do too.