Yes, Marijuana is legal for Medical and Recreational use as of January 1, 2017. However, it seems to be slow to be for sale at the Dispensaries because local Government has not set up the rules of trade as of yet.
It is not legal to smoke Pot legally anywhere in Public in the State of Nevada. Do People do it? Absolutely! I walk through half the Casinos on the Las Vegas Strip DAILY and I can say that I have walked by People smoking Pot at least every other day, on the sidewalks. Nobody says a word. I have even spotted People smoking Marijuana inside a Casino and in no hurry or no panic. Like most Las Vegas laws there isn't much enforcement. Just like carrying a glass container is illegal it happens all the time. It is what I call selective enforcement. If You do it right in front of a cop they will feel disrespected and give You a citation. If You mind Your own business You probably will not have any problems.
You are really pushing Your luck if You fire up a blunt inside a Casino, the reason is any place that has a gaming license must obey Federal Laws, not State Laws. Smoking or possessing Marijuana is still against Federal Law and likely will be for a long time. So if You decide to fire up a blunt on any Casino property, You are putting the gaming license at risk of the Property You are standing on. The Casinos have more reason to stop You and even arrest You for smoking pot on their property than do the local law enforcement doing so on the public sidewalk.
In the Video below a busker "appears" to smoke Marijuana, looks and smells like it as She continues interaction with Vegas Visitors. She is doing pretty well with Tips. See what happens in the second Video.
Approximately 20 minutes after the smoking in the first video We now have the Drama Video. Notice no more work being done? Remember the commercials about Marijuana a decade ago? I smoke Marijuana and NOTHING happened to Me?