We all would like a free upgrade. Although it happens on occasion, it's not common at Disney hotels.
Disney hotels run at a high rate of occupancy and have people coming and going every day, so there's not as much flexibility as there might be at other hotels. We also understand that the room assigner is not able to make room upgrades (that is, the computer will not allow it) unless all rooms of the guest's room type are unavailable.
If you are requesting a hotel room via our Room Finder tool, we recommend that you only request the type of room that you are paying for. That allows the room assigner to try to meet your request; if you request a more expensive room that what you have booked, you are likely asking the impossible.
That said, you're free to request whatever you'd like. And if you're interested in a paid upgrade, you can certainly ask at the front desk upon check-in to see if anything is available.
Keep in mind, of course, that our Room Finder tool does not guarantee anything. We try to send the fax to your Disney hotel, but we cannot control what (if anything) Disney does with it. We have heard plenty of success stories, but do not count on getting the room you requested, and certainly do not get your hopes up for an upgrade.