I have been using bare fingers to change out tubes but just read somewhere that oils from human hand will shorten the life of the tube. Is this correct?

I have a white tube glove, but rarely use it. How are you going to remember to put the glove on every little time you swap a valve?  The glass is impervious to the elements and the vacuum is inside. How a fingerprint could in any way affect that is beyond me.

Good point rmt. I have never had one break in my hand so never thought of this.

I also use a rag to take them out a lot of the time as they are hot. Then I usually put them in with clean hands, but over time this shows, at least with tubes that get rolled a lot, the finger grease burning on to the tube. It seems to clean right off though for the most part as long as it does not go too far.

I guess if you have high dollar tubes you intend to trade at some point, it would be wise to use a cloth or glove every touch, and avoid those fragile NOS markings.