Is a small amount of water coming from the auto exhaust a bad thing?

It's normal condensation. That's why you can see your exhaust more in the winter when the air is cold. Just a little side bar fact: people that usually drive short distances periodically (like if you work a couple miles from your house) have there mufflers rust a part quicker due to the fact that the condensation doesn't get blown all the way out of the exhaust so it causes internal rusting. It's condensation unless it smells 'sweet'. If it has a definite anti-freeze sweet smell then this would suggest a leaking head gasket. If it's just a little water, especially during short drives, don't worry about it.