We live in Las Vegas and I have four kids, ages 14, 12, 8 and 8. They love it here. In fact, we are getting ready to head down to the Strip for a bit right now! The twins want to see the lions and go to M&M World, so off we go.
There is plenty for kids to do and see. It does require advance planning and research, but it can be a fun vacation. Obviously you know your kids best and would know what sort of things would interest them but here is a very good list of attractions that are kid friendly:
http://www.vegas.com/attractions/kids.html
I think people get concerned over the moving billboards, which do have pictures that leave precious little to the imagination, and over the cards handed out. This is where each parent has to make their own decision. I don't make a big deal out of it, and it's never been an issue in our family. I had some questions about all the Gentleman's Clubs from my oldest, but I answered them honestly, and that was that.
There are some fun shows for kids too. My two oldest loved KA, and we recently took them to see the Popovich pet comedy show and the Nathan Burton magic show.
In the end, it's a personal decision for each family to make, but there ARE things for kids to do. Have fun planning!