One of the things that drives me crazy is seeing a Master/slave relationship portrayed as Dominant/submissive. The two relationships are NOT interchangeable, at all.
I'm going to post a link to a site that has probably one of the best explanations of the two terms, and I urge anyone who wants to write a real D/s relationship to read this.
A Slave is Not a Submissive
The author uses rather silly gender neutral pronouns, granted, but the definitions are superb.