How busy is Easter time at WDW?
I've heard Mardi Gras time over there has gotten quite busy over the years. I'm not surprised, as TONS of people from here go there at that time.
I haven't been for Easter, but I can imagine it can get quite crowded. Easter is also hard to predict because there are lots of different weeks that people get off for Spring Break. I worked Thanksgiving and it was busy. For Christmas/New Years we were busy for like 3-4 weeks straight. It's all about hitting just the right time. When I'd go to the parks around Christmas, all you could do was walk around unless you wanted to wait in line. The best thing to do when it's busy is to get to the parks early, take advantage of Extra Magic Hours, and definitely utilize the fast pass system.
April should be fine though because Easter is in March. The only time it should get really busy is like the last week and that's because of Grad Nite. EPCOT may be busy also because of the Flower and Garden festival.