I have been fascinated with the richness of Tarot symbolism since an early age, and in the HBO series ‘Carnivale’ I was literally blown away by the gorgeous intro sequence:
http://www.youtube.com/watch?v=wNRs0Z61gu4
There are many confused associations with Tarot in people’s minds, so I thought I’d try and clarify things a bit, or at least offer my take on the situation.

Tarot cards are a collection of concepts in symbolic forms, representing aspects common to human life over the ages. Themes associated with the mind, body, heart and spirit are included. So what is wrong with this? As Alice said ‘You’re nothing but a pack of cards!’
http://www.victorianweb.org/art/illustration/tenniel/alice/12.3.html
Well, the modern 52 card deck bears a close correlation with the Tarot card minor arcana structure – so right from the start there is more than meets the eye!

Essentially, the Tarot is a very powerful tool for meditation, and the very act of self-reflection is potentially risky but also beneficial. Meditation itself can reveal unpleasant truths as well as beneficial revelations. Some would claim that Tarot cards ‘tell the future’, and the consequences of foretelling your own death have been explored in various horror stories and films. To this I would say, if a person insists on putting themselves in dangerous situations, is it so unreasonable to say that they are in danger? The ‘future’ the Tarot can tell you about is via the truths it can uncover in the present. Simple as that. Forewarned is forearmed, so make that important life-bettering decision today. If you start to believe the Tarot does more than that, then my advice to you is be very careful!

The card of ‘Death’ in Tarot actually means change or transition – which underlines the importance of being conceptually ‘flexible’ to avoid being constrained by your own limited perspectives. Tarot can help as a form of mental yoga! The card of ‘The Tower’ is actually one of the most unpleasant cards AFAIK, simply because it identifies periods of such dreadful upheaval whether or not the outcome is for the better.

In a Tarot reading the cards are laid out in positions of significance, such as representing you, present influences, how other perceive you, your hopes and dreams etc. The cards then become windows into your psyche, snapshots of your life for you to reflect on and interpret. Unexpected combinations and associations encourage you to explore new avenues of thought, but all the time you are interpreting the cards, or the reader is interpreting them with your input. Your personal feedback is essential.

This leads to the unfortunate situation where a person who disapproves of Tarot expects you to tell their future and read their mind without any assistance other than a frosty tight-lipped silence. Tarot is not mind reading – at least, not reading another person’s mind! It is about learning to read, and know, your own mind and motivations.

One last point: If human nature changes, wouldn’t we need new symbols to be introduced? My initial suspicion is that the meanings of the existing cards would be able to change to accomodate such things. From experience, any model should acknowledge its limitations and permit room to change and grow otherwise it risks becoming outdated. The inherent ambiguity in reading the cards does exactly that, for better in providing this flexibility, and for worse in permitting confusion. Even then, this ‘confusion’ often serves to stimulate the mind in useful ways!