we have usually gone in Early June for many years (I am a teacher). The bad things first: It is hot and humid. Plan on going early in the mornings, take a pool or nap break in the afternoon, and return in the evening. The Second bad thing is that it rains about every afternoon for about an hour to an hour and a half. In the heat it acutally feels good, but it does add to the humidity.
Good things: Hours are longer, or at least starting to get longer. Crowds, while larger that January or February, are still not at peak because most of the East Coast is still in school. Therefore, prices are not at peak, but regular rates.
One more thing that is not a bother to my family, but is to some is the first weekend in June is usually Gay Days. My family and I have been at WDW during that time and have never had problems. Hope this helps!
