The "value" of what a point represents cannot change.
A lot of people confuse what they are actually buying. A lot of people think they are buying "points" from Disney. Disney has done a great job at making it look this way. What every
DVC member has actually purchased is a percentage of unit (a room or collection of rooms). For the purposes of using your membership, your ownership percentage is represented (conceptually) by a number of points.
Since Disney has sold you a percentage interest, they can't sell more than 100%. Which means there is a maximum number of points that can be sold for each room. This also means that there are a certain number of points (over the entire year) for each room and the resort (adding all the rooms together).
Here is what Disney can do:
1) They can add points to a resort only by building new rooms.
2) They can re-allocate the points for the entire resort (up to 15% each year) and redistribute them amongst seasons, views, room sizes, weekdays/weekends, and types.
Here is what Disney can't do:
1) They can't create points out of nothing. Remember that points are just a representation of your ownership percentage. They can't simply add more points to the system, because then the total ownership percentage that is sold would be greater than 100%. This means that the "value" of a point can't ever decrease. You'll always be able to book the same percentage of the resort, compared to other members.
Other thoughts:
1) DVC is a timeshare. It's sold to very close to 100% capacity (every room booked every night for 50 weeks per year). If they find that points aren't being used to book every room based on that and rooms are left vacant, then points are going to HAVE to be lost because now there are unused points in the system and not enough rooms to book them with. They have to balance out the supply and demand. If the point cost of your particular stay has gone up, then it simply means that the demand for your particular stay has gone up as well. They are required to balance it out. They do this by increasing the point cost of certain stays and lowering the cost of other stays.
2) As the DVC membership gets older and the demographic of a "typical DVC member" changes over time, then so are the "in demand" seasons. For example, it would be easy to argue that as people who bought DVC get older, kids grow up, move out, etc. that there travel habits will change. Suddenly, they don't need to wait for school to be out, they can go any time of year, they like to go when it's not as busy, point costs are less, etc. These people will slowly shift from being summer and out of school travelers to off-peak travelers.
Disney will be required to reallocate the points for travel periods, as (within the scope of DVC) the "peak" periods change. Which is what they are doing. They are responding to changes in the travel habits of a "typical DVC member". Members' kids are growing up and moving out, they are taking advantage of the lower point costs, and the travel habits are changing.
You can see this using the links someone else provided:
Original OKW
point chart:
http://photopost.wdwinfo.com/data/500/OKWpoints94-95.jpg
2011 OKW point chart:
http://www.wdwinfo.com/disney-vacation-club/OKW-Points.shtml#oldkeywest
You can see that a week during the "Adventure" season went up, a pretty good bit, across the board.
The weekly point costs for the "Magic" season went down across the board. The magic season is the largest season.
Also, as members start to retire, the need for them to travel on the weekends has gone down too, so demand for weekday stays has gone up, because of lower point cost. Which is why the point costs for weekday stays has gone up and weekend point costs have gone down.
So in conclusion: The cost for any particular stay can go up...your points may not be good for a certain room during a certain season (as demand for that room during that season goes up)...however, your points would then be good for a different room and/or different season. However, the overall value of your points can not go down.
