The Segways were a real blast. You head over to Epcot guest services to sign in and they take you to a special training room. They explain the concept, safety and general directions. You watch a 5 minutes movie and then they get into the nitty-gritty. You don your lovely head gear (helmut head comes to mind) and then they teach you-hands on how to use it in great detail-you can stop at any time if you feel at all uncomfortable, but it is really very easy (I am not the most co-ordinated person on this earth). We had no problem at all. Then they take you out into Epcot (before the World opens) and give you a tour and a description of each of the countries-very informative. You do little challenges like going through mazes, over bridges in and out of pillars etc.
We had such a great time we didn't want to take the Segways back!
Since our whole group (9 people) had arrived 20 minutes early we got the extra time on the Segways. Total tour for us lasted about 2-1/2 hours.
Well worth the $ and you do get an annual passholder discount if you have a WDW annual pass.
You receive a special epcot Segway tour pin at the end of it.
This is a tour we will definitely take our kids on the next time we go.
If you are taking the cruise as well I recommend you do the Segways before the cruise since we had real sea legs for about 5 days afterwards. Not sure I could have handle the Segway tour after the cruise but had no problem before it.