Ethical hedonism isn't an
oxymoron, as some people would insist. Ethical hedonism is the
moderate approach to hedonism; what
most people think of as hedonism is the
extreme end of the philosophy.
Common beliefs of ethical hedonists include The Golden Rule (Do unto others as you would have them do unto you) and The Libertarian Principle (Anything that a person does that doesn't affect anyone else is their own business).
In essence, the difference between this and the stereotypical hedonism is whether you have respect for others or not.