In the last two years, I have received "noticeable" upgrades (meaning that I can tell I was upgraded, not just a meaningless upgrade from one room to a slightly better room of the same type) at one hotel.

At the Renaissance Harbour View in Hong Kong, my gold status usually upgrades me from a "garden view" room looking out the back of the hotel over the swimming pools and tennis courts to a harbour view out the front of the hotel.