It also is good to know that The Wheel of Fortune is the card halfway through the Major Arcana, and is the gateway from the materialistic, practical first half into the more spiritual, abstract latter half (Barbara Walker Tarot 10).
The silver ball going around symbolizes the arbitrariness of fate. Sometimes life doesn't rise and fall in an expected rhythm.
The Celtic Deck's Wheel of Fortune also shows two men, one rising and one falling. Looking closely at the man going up, one can see that he is climbing. This could mean that the questioner must strive and work to achieve his desired fate, and that it is in the questioner's power to create his destiny.
Keep in mind that I am only writing what I am seeing in this card on this particular day. When you look at the card, you may be focusing on something else. Or, you may be focusing on the man on the upswing, and seeing something totally different. That's wonderful!
An interesting aspect of Barbara G. Walker's Wheel is that it could be seen as rotating counter-clockwise, as the figure on the left with the head of an ass is falling down, while the figure on the right with the head of a hawk is climbing up. While a clockwise movement is associated with the Sun, masculinity, and the bringing in of energy in Wiccan tradition, counterclockwise is the feminine and repelling.
Barbara G. Walker writes that the figure with the Hawk head is Horus, the ancient Egyptian god of the Sun, and the plummeting man with the Ass head is Set, who represents darkness and the sterile desert (Barbara Walker Tarot 10). Using the cards and your own intuition, you can decide whether the questioner is Horus or Set in the situation, and whether it is the right time to make a move and achieve an end, or to wait and avoid disaster, or to expect delays or obstacles.
At the top is Justice, reminding us that our actions always have an effect, whether now or in the future. She keeps track of our karmic debts, and makes sure we are rewarded through the Ankh, representing love and protection, or punished through her sword.
The mention of karma leads me through association to the concept of samsara, which is the great cosmic wheel of life. In Hinduism, being in samsara means that the soul is still going through the process of reincarnation, and therefore has not reached the enlightenment necessary to enter Bhraman, or the Great Cosmic Spirit. If The Wheel of Fortune comes up in a reading, it may mean that the questioner is reaching an epiphany, or that the questioner is not quite ready for an undertaking.