As I understand it, yes, thats the bell housing, and yes, tranny fluid can leak from those vents. I believe that probably indicates a bad torque converter seal. Make sure, however, that the fluid is actually leaking out of those vents, rather than just being on the outside, which would mean a leak somewhere else. I don't think motor oil can leak out of these vents, but it could certainly be on the outside. You say that they are just wet though, not dripping, and if you don't have any significant loss of transmission fluid, I wouldnt worry about it. I seem to recall that mine were usually a bit wet, but that doesnt necesarily mean that its normal.