Impressions after riding a Segway HT
Dan Bricklin has written a nice article on what it's like to actually ride (drive?) a Segway or "Ginger". His discription of how the Segway feels to ride was interesting. He said it feels as if it has four wheels, not two:

"Looking forward, you don't see the two wheels. In my mind, it always had four. (How else could it feel so stable?)"

"It always feels in control, never like it's coasting. That, and the low center of gravity (80 pounds under me rather than me balanced on a lightweight bike or something), distinguished it from other small personal transport devices. It reminded me of my few times on a jet ski on a lake (without the bumping or waves): When you stopped telling it to go, it slowed down very authoritatively."

After reading Dan's review I could see my mom, who has MS that affects her balance and endurance, riding a Segway. It seems like a viable alternative to a wheelchair or walker. My guess is the Segway won't be adopted widely as an alternative to cars, but Bricklin's final statement has a ring of prophesy:

"Gary hinted a bit to us about Segway's Stirling engine that with or without the Ginger could have great impact around the world. Remember, this is just the first general product using some of these technologies. There will be many more. Think of the Segway like the first uses of the microprocessor in a calculator, before the personal computer, PDA, flat panel LCD, DSP, GPS, etc. On my run when I saw a Vespa-like motor scooter putt-putt-putting along, I thought of the abacus."