I guess it depends upon when you are going to be there... and how busy they are. From what I've read here, the best way to ensure you won't get a free upgrade is to ask for it.
You may ask as you first check in, before your actual room has been assigned, what you would see from your standard view room... and what is seen from a water view.. and as they say what you can see, you can exclaim how lovely that must be.... and an "oh wouldn't that be simply wonderful!" From there you may be able to get one for the same cost or perhaps just a few bucks more.
DW and I stayed at the YC last October. It was wonderful. Our room was on the top floor (concierge) just over the doors to the lobby looking right down the pier where you get on the boat to epcot. And if i find the brat who threw bbq sauce all over our balcony we're gonna see if they can fly like peter pan right off that balcony.... hehehehehe
Darian
