I’ve been using Scrivener for my writing and I’m happy with it. I’m a long-time hater of Word, so finding Scrivener was a big relief. The main reason I like Scrivener is because of the export, or compile, tools. With a simple dropdown menu I can export to mobi, epub, pdf, word, and many other formats. So far, all the output I’ve seen works as it should.
As far as the writing itself goes, it’s not much different than Word or any other text editor. You type, characters appear, you save.
I’ll post a more detailed review of Scrivener one of these days.