Personally, I think people are starting to take things way too far. For instance, the woman specifically said she has difficulty getting up from a seated position and so she can't use a wheelchair, yet she wants to go to Disneyland where 99% (maybe a slight exaggeration) of the rides require you to sit in fairly low seats? What next? Should Disney have to redesign every ride so that she can ride it?
This reminds me of the amputees who just recently sued Universal. I understand their condition. I do empathize with them. I have a friend who has so many rods in her back, she can't be jostled around. Does she go and complain that she can't ride anything at Disneyland? No, she just knows that she can't enjoy the park, so she stays away.
If the country keeps moving in this direction, within the next 20 years, I can see music and movies being banned because blind and deaf people can't enjoy them the way everyone else could.
Now, specifically regarding the Segways, I don't think it's a good idea. I get run into all the time by people in wheelchairs, strollers, etc. I can't even imagine having people zooming around in a Segway trying to weave through the crowds. Not to mention, on crowded days, I'd think it'd be pretty hard to keep a Segway stable enough to not run into someone else.