Nope, but I could spend a week there and not get it all done. There is TONS to do there. Aquarium, Spaceship Earth, Mission Space, Figments new ride, Land Pavillion with cool things, and that doesn't include all the countries! Each country has some shopping, great restaurants, usually outdoor performers, Kids stations to stop at and make things, and some have rides and shows inside to visit. Epcot is pretty spread out, too, with lots of beautiful things to look at and walking... it's not all smashed together.
It takes me all day to do the World Showcase alone, if I want to really stop, learn about the country, sample some food, shop, ride the ride, see the show, and visit wtih some of the wonderful CMs that are from that country. Plus eat a few meals!
The nighttime show (Illuminations) is spectacular, as well, but people line up pretty early for that, and it cuts into park time.
But Epcot is my FAVE park, so I'm partial to it =)
I suppose if 5.5 is all you have, then that's all you have... do as much as you can.