As a former CM at Disney and ex-Tech Support guy at Microsoft (and a few other companies that used a lot of Windows based products), I can maybe shed a bit of insight (but no actual first hand facts, heh)...
Prepare for boring tech explanation:
On the Microsoft end, Disney is more than likely using OEM licenses. If you ever had an OEM version of Windows and tried to call Microsoft for support you probably reached someone who worked in the same position I used to telling you to contact your computer's manufacturer for support. The reasoning is, Microsoft sells OEM licenses (in effect "copies" of the software - won't go into detail on that here) and the only major difference between that and a retail copy of the software is that the OEM "distributor" agrees to provide support rather than Microsoft. This technically saves Microsoft money in having to pay techs to deal with someone calling for support.
What this means on the Disney side is that a big company, such as Disney with their own IT department, doesn't need the tech support that Microsoft would provide. Therefore on that end, it doesn't affect them much. On top of that, obviously Microsoft wouldn't be providing updates and patches, but in all reality they've patched just about anything they can on that program (see, "polish a turd" reference), so it should be good for the foreseeable future. In my experience as an Entertainment Tech for Disney, they don't update ANYTHING, software or equipment wise, until they are pretty much forced to. So basically at some point, yes, it will be upgraded, but not anytime in the near future as most companies will milk everything they can out of a system before doing the expense (including potential hardware upgrades, training hours, etc) of switching to a new one.
Anyone still awake?