It's a tour, it is something that you have to pay for in addition to your park entry.
The cost is $80 per person but discounts are availbe for AP, DVC, DV holders.
You can check out some reviews at
http://allearsnet.com/btp/tours.htm#seg
It's two hours more or less, where the first hour your learning how to ride and the second they take you into World Showcase at Epcot before it opens to park guests in the morning.
We plan on doing it in July when we are there since it looks like a lot of fun.