We just got back from Vegas last night. I still don't see any way I would want to bring any children there. For instance I saw two women wheeling their babies in strollers through the smoke-filled Flamingo casino, not the best environment for passing through. The strip was littered with cards advertising escort services. The sights (Eiffel tower, New York, NY, the Excalibur, Luxor, etc.) would be great to see once but then what?
As part of a poker room tour we went into Circus Circus (which the bartender at the pub across the street called her least favorite because of children running in and out between the slot machines) and inquired about tournaments. She recommended one further up the block at Stratosphere. When we said we'd walk up and check it out she said "No, I wouldn't advise you to do that. It's not the best area to be walking in." In case you aren't familiar with the area the newest HGVC location is in between those 2 casinos.
I would say Vegas would be a great location to use as a base camp if you want to tour the Grand Canyon and other sights the area has to offer. But the family-friendly claim still escapes me.