I also believe it's crucial to find your own thing rather than milking what's already been done. As much as I enjoyed Tolkein-like sword and sorcery novels there eventually came a point where I couldn't stomach them anymore. It was all elves, dwarves, wizards, men and I wanted something different.

Which, yes, can't be said for every reader out there - there will always be an audience for Tolkein-like fantasies. Still, the more you try to do your own thing, I think, the more your story stands out in the reader's mind (thus getting the reader to tell others about the book, who then tell others and so on. I didn't get into Harry Potter because of ads or commercials. I got into it because my dad sent me a copy after he read it).