There have been a lot of posts about this. We were at WDW this past year at the end of May. The crowds were surprisingly large (many more people than when we visited in July/August!!), the temps. were hot (as expected), etc. I've posted in the past that when we decided to extend our trip through Memorial Weekend, we found that all hotels within 20+ minutes of WDW were completely booked! Dh perservered and continued to call several times each day throughout the week and ended up catching a cancellation at CSR. Afterwards, we wished he hadn't. The parks were too crowded to enjoy with young children along. MGM was unbearable by late Friday morning. (Of course, it was a Star Wars Weekend, too.) By noon on Saturday, MK was shoulder to shoulder people. Epcot was nearly as bad on Sunday. Since this is far from our only visit each year, we will continue to go at this time of the year (when school lets out).