dsnymomof4...I understand your situation!
Our DS has started to grow weary of trips to WDW and we've only been 4 times since 1999.

I think having gone twice in 2005 though was what may have done it for him. Since it was our first year as DVC members, DH and I got all excited about getting to make the extra trips thanks to our DVC membership, so I can understand Grendalynn's concerns. But, just because our DS isn't "into WDW" doesn't mean we'll be selling our DVC points...it just means we are looking into the other options with our points.
I also think, like many posters on this thread have stated...it's that tween/teen thing. I remember when my sister was 16 and we did a big family camping trip north thru Canada and 5 states...she was miserable and Mom threatened to put her fanny on a bus home everyday. She missed her friends and didn't want to be on no stinkin' family vacation.

Also, for our DS, an only child, he'd rather be able to do some of the fun things at WDW with a friend than the parental units...

...and we are starting to debate that option for future trips. I know last year when my Dsis, her daughter (2 yrs. younger than DS and also an only child), DS and I road tripped to Virginia for a family baptism, that DS had a great time. He and his cousin got along very well even though his cousin is a girl. For us, this may be a great option...Dsis and her daughter are huge Disney fans...matter of fact, Dsis told me the next trip we go to WDW for Christmas to let them know and they'll go, too.
I think that what DisTeach1 posted is valid for some, but not for all. I do not think that just because my DS doesn't want to go to WDW again for a while means in any way that he is a spoiled brat. It just means that he knows when we ask him his opinion for family vacation ideas that his opinions do mean something. I can't speak for anyone else's family, but for us, a family vacation means not only does the whole family go, but the whole family gets a say in the planning. For example, when we started to plan a trip for this June, we thought we might just head to WDW (use those DVC points), and since DS isn't into the parks, we'd just hang out at the resort pool, enjoy the spa, visit some of the other resorts we haven't seen and go to DTD...try to relax more

than go-go-go in the parks...which is the part that DS really dislikes. Well, when we talked more about the trip, we realized that DS really wanted to see more of the world than just WDW, Orlando, and Florida beaches. (In all honesty, I can't blame him...I wanna see as much of the world before I die, too.) Actually, this is a whole family thought...see as much as we can.

So, since I've had the wish to see DL at least once, we talked it over and are going to California this trip. (Only DH has been there and it's been over 25 years since.) So, we are pretty excited...staying at the Grand Californian, which is suppose to be a fantastic resort.
The other factor that I believe is involved, and other posters have hit upon, is the only child syndrome. Both DH and I have siblings...DH's are closer to his age than mine, so he remembers great family vacations, while my sisters are 16, 12, and 6 yrs. older than I am. I have never been on a family vacation with both of my parents and all of my siblings...for the first 10 years I remember vacations with the sister 6yrs. older and my parents, which were great. But by the time I hit the tween/teen stage, it was just my parents and me...totally boring since my parents were in their mid to late 40s by then and didn't always want to do things that really interested me. So, I got lucky and by 4th grade I was getting to bring a friend along...not on every trip, but some of them and it made the world of difference. My parents weren't being bugged with the "I'm bored...what can I do?" and they were able to relax more and have a good time and because I had my friend, I wasn't bored and had more fun. And as for the quality family time, well, it was still there...at least for me because I still have wonderful memories of spending time with my parents, who were more relaxed and able to enjoy the time we spent together...and the friends I took had been my friends for so long that they were like another member of the family anyway.
So, I guess after adding my 25 cents worth, I'm just trying to say that, dsnymomof4, you are not alone!

There are many of us moms who love going to WDW, but our tween/teen kids don't anymore. Also, that for each family it's a uniquely different experience as to the why's and wherefore's of the situation and because of that we've all gotta work out ourvselves what is best for our families.