The funny thing for me was I didn't want to go. I had no interest in gambling so no interest in Vegas. I found I loved the city, for many of the same reasons I like theme parks.
One list I looked at ranked Orlando as the biggest convention city in the US. The theme parks are the biggest draw, but kudos to Orlando for building so much convention space (Universal is working hard to catch up) . Beaches, warm weather, reasonable prices and so much more to do also help.