From what I understand, it really depends on availability. We really wanted a resort view balcony room at The Swan, and from my reading here I got the sense we were really rolling the dice to depend on an upgrade. So, I paid a few points to guarantee a resort view balcony room. There are people on this board who are Platinum and not received an upgrade at certain times.
We are headed to the Swan on Saturday for six night, so I will make a note to report back on any upgrade when I do a report here of our resort experience.