Our wedding wasn't in EPCOT, but we did bridal portrait pics there. I'd recommend lurkyloo's Passporter e-book to explain what it takes to have an EPCOT wedding (or read her TR, since her wedding was in Morocco). Or check the other PJ/TRs because there are several recent or upcoming EPCOT brides on here.
Here's a thread with a recent bride who did an EPCOT bridal shoot.
We were married in the Japanese Pavilion at Epcot and it was amazing! I LOVE the Epcot setting.
I also recommend the PassPorter Disney Weddings e-book. It really helped me with the process of planning an Epcot wedding and right through to the end too! I highly recommend it. It's full of ideas and checklists and will really help you learn more about your options of planning any Disney wedding (including Epcot).