We have done NYE in Las Vegas a couple of times, the most recent being a couple of years ago. We stayed at NYNY and attended their Bridge Bash out front. We got a good view of the fireworks shot from the MGM I believe.
All in all I don't think NYE in Las Vegas is any worse than other places I have spent it. A few things I have learned:
* It is much easier if you plan to do dinner and activities at the resort you are staying at, or at least fairly close. The less you have to go back and forth from other properties, the easier it is.
* Starting at about 6pm many of the properties start limiting who can come in to the property to registered guests or those who have reservations for dinner, a show, event, etc.
* Many of the properties have all-inclusive NYE parties, dinners, etc.. I found the year that we did one of these so much more fun than the year we did one of the clubs (and considerably less expensive).
* There are stupid, drunk people everywhere on NYE (it isn't called Amateur Night for nothing. Don't let that stop you from giving Vegas a try. It may not be your thing, but only you will know that after you give it a go.
Enjoy!