I like to describe it as when the boundaries which you imagine to separate yourself from the universe disappear, because you realize they were never there to begin with (except in your head). In a way, ego loss is a loss of self. But at the same time you're not losing anything, you just discover that you never had it to begin with.

In such a state (at least in the times I've experinced it) it becomes impossible to judge others, because you realize that as part of the universe there's nothing separating them from you.