I think it depends on the family. The memory maker photos overall were not as good as the photos I took, but I'm an experienced photographer with some good equipment, and I do't mind carrying my camera in the park. In fact taking pictures on my trip is part of the fun of vacation for me. If you don't enjoy taking pictures or want to travel light, it may be well worth it. The MM photos typically weren't well composed and relied on heavy use of fill flash, so they're not something I would hang on my wall, but they did the job of recording our trip.
I do think it's fun that MM offers video now. They started this just before our last trip and we got video from ToT. I was able to include a clip of that in my trip video. Also, there are photographers at the water parks. I took my DSLR camera there but didn't have it out a whole lot, so we got some shots I would not otherwise have gotten.
We split MM with another family that we travelled with, so for us at half price, we got some use out of it. But I probably won't use it again.