I have received a few notes from practicing Satanists, saying I am mis-representing their faith as one which worships evil, sacrifices animals, etc. My intent is to dissociate Wicca from any of those groups, and not to associate Satanism with the other two.
I will not make any effort to try to make Satanism look good, because Wiccans have their own PR to deal with, and because I don't agree with the ideology of that path. Disagree or agree, it would be wrong for me to work to improve the image of my path, at the expense of another.
So for clarity sake, here are a few of the major differences between Wicca and Satanism: (you may go here if you wish for information on satanism to compare with.)
Satanism does not explicitly prohibit harming others, Wicca has that law as a foundation. (Satanism does make it's adherents responsible for the results of their actions however, making harm unwise most, but not all, of the time)
Satanists are primarily concerned with their own needs, and places no emphasis on helping others, unless it can help their own needs, or the person is truly deserving of help. Wicca places importance on ones own needs, and on the needs of others (ie: you can't help others for very long if you let yourself die saving someone from a sprained ankle).
Wicca is a nature-based religion, Satanism does not have nature as a part of it's central interests.
Satanism embraces harsh vengeance against those who have wronged you, Wicca believes in harm only when necessary to protect yourself, or others.
Modern Satanism was founded by Anton LaVey, Wicca was founded by Gerald Gardner.
If anyone from either side feels this is a mis-representation of the two communities as a whole (not just a few cases or individuals) feel free to e-mail me... -Matt