I kind of do the opposite of mr. Zigzag. When I shoot night shots I shoot almost wide open with a low ISO setting. and let it go for 30 seconds. I set the focus on some distant light and then put the camera on manual focus and leave it. Something like this tutorial. If I can't get it to focus I just manually set the focus to just past infinity then just shoot away. I like this shot because you have too look for abit to see the reflections, but once you notice them they are really obvious. :)
Man, I miss NashVegas! Lived there for about 5 years in the late 90s. Would love to move back. Nice shot. Can't wait to see what the Signature Tower is going to do to the skyline! :-)