I guess the answer is: it depends how what you do AFTER the venting that matters most!
Mary Steinhardt, professor at the University of Texas (website below, if you are interested in learning more) discussed in our graduate courses some great insight in two ways of coping:
1. Emotion-focused coping
2. Problem-focused coping
Emotion-focused coping includes venting, crying, distracting ourselves (sleeping, exercising, eating, working on another project). Venting, and these other coping mechanisms, definitely have their place, and can help you blow off steam, gain perspective, and feel calmer to move onto the next step: problem-focused coping.
Problem-focused coping moves away from "just venting", and actually puts your words into action. Did any ideas come from talking about your problem? New insights? A new way to look at the problem (reframe) or new perspective? Are you able to change the problem, or do you need to let it go?
Bottom line: venting is OK (even healthy!), as long as it leads to action and is followed by problem-solving. Venting with the "correct" unattached, uninvolved person can help avoid situations where this talking can lead to "gossip", for instance, you may want to avoid venting with a co-worker about another co-worker.
I love this so much, I have to share this inspiring story:
The Two Wolves
An old Cherokee was teaching his grandchildren about life. He said, “A battle is raging inside me…it is a terrible fight between two wolves. One wolf represents fear, anger, envy, sorrow, regret, greed, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride, superiority and ego. The other stands for joy, peace, love, hope, sharing, serenity, humility, kindness, benevolence, friendship, empathy, generosity, truth, compassion and faith.”
The old man looked at the children with a firm stare. “This same fight is going on inside you, and inside every other person, too.”
They thought about it for a minute, and then one child asked his grandfather, “Which wolf will win?”
The old Cherokee replied: “The one you feed.”