UPDATE EDIT 4/12/14
This changes everything...
Las Vegas has many "landmarks" by general accepted standards that would not necessarily mean they are landmarks per Waze guidelines. I imagine other resort towns in Nevada are similar in nature. I imagine part of the purpose of restricting the landmarks is not to stifle the desire of new editors to contribute. I do think the general consensus of Waze Champs is that in some way a landmark must contribute in some way to the overall mission of Waze which is to improve transportation. If you haven't read them, I gave 3 landmark links below. Sometimes I think we might desire to put in a popular restaurant or tourist destination in Las Vegas for instance. However, unlike our Google owner our purpose should not be in cluttering up the map with landmarks which do not stand out in contrast to other similar destinations. A landmark should actually serve a purpose in creating a visual guide on the client map we use on our mobile devices. What I mean is that it seems to me that while a destination in Las Vegas on a gigantic scale might be a landmark in a field in Iowa, it doesn't stand out in contrast to other similar destinations immediately adjacent and might actually clutter the map visually and certainly a long title or name on a landmark will clutter a map when concentrated in LV. There also seems to be some consensus that at some future point Waze might be able to improve their revenue stream by making a commercial destination more noticeable on the client map through a little flag or banner ad. (I personally hate non relevant ads popping up all the time.)
What I'm hoping for here is a discussion of what landmarks besides what is discussed in the links below to what should be acceptable in our unique state of Nevada. Instead of focusing on landmarks of course our real purpose is to improve our driving in our editing and clutter on our mobile devices likely doesn't help. There is so much to do in Las Vegas to clean up the maps, (especially on the side streets) it might be more helpful to learn how to edit by reading up on Wiki map editing practices, myself included.
Ultimately for the benefit of new editors, before heading out to add a whole bunch of new landmarks just to have fun or something to do I would say to you consider when in doubt, check with your area manager, or at least a more senior editor who is more than happy to give you some guidance in what is acceptable here. The frustration of setting up a landmark in mass quantity or size to just have your area manager delete it might make you think twice about getting too jolly on "landmarks" with your fledgling and ever growing skills. USA Landmark WikiUSA Landmark general discussion forumLandmark Country Managers discussion forum