Worms do love wet leaves. If your plan is to spread the wet leaves thickly all over the surface of your bin you might end up blocking the oxygen. You can either spread them over part of the surface so that the worms have a place to escape to or you might mix them with cardboard or egg cartons so that the leaves aren't a slimey, matted mass. I have shredded leaves (you didn't say if yours were shredded or whole--shredded won't mat as much) that I mix with cardboard, etc. and some vegies. I put this mixture in a bucket and mix it each day for a week. I then spread it on the surface of my bins--the worms love it!!

Go for it with the leaves, after all, in the wild this is their habitat if I'm not mistaken.