It's a great in that it allows you to store all of your research data and information (including pictures, soundtracks and movies) in the same file as the document you are writing.)
Scrivener is not a word processor, although it can do the basics of bold, italics and underlining, etc. Instead, it allows you to write a scene, or a collection of scenes, in any order that you like. What makes Scrivener better than a word processor, is that you can move huge chunks of text around, quickly, easily and without cutting and pasting. So, if you decide that scene 14 would be better as scene 2, you simply drag and drop. Here's how the programme is described by the developers:
Scrivener allows you to split up a long text into smaller, more manageable chunks (chapters, scenes, main points - how large or small is up to you) and to edit them independently or together as one long document. Its structural tools include a corkboard and an outliner for rearranging the constituent parts of your draft, so that you can plan your work in advance or get an overview and restructure it after the first pass. You can also refer to research documents (such as images and PDF files) by having them alongside your text as you work.
When your manuscript is complete, you can compile it into one long document for printing or for exporting to a word processor such as Microsoft Word.
To find out more, visit the Scrivener website at http://www.literatureandlatte.com/index.html
There's a great video demonstration available at http://www.literatureandlatte.com/videos/ScrivenerIntro.mov
Why am I mentioning this now?
Well, the second version of Scrivener is about to be released for Apple Mac users, but in 2011, for the first time, there'll be a version for Windows users too. And, any Windows computer user who tackles this year's NaNoWriMo event (National Novel Writing Month in November) and successfully completes the required 50,000 words during that month (and gets their verification certificate) can obtain a 50% off discount voucher of the Windows version when it is released early next year. (A single license will be $40, so the voucher will drop it down to $20.)
To find out more:
Scrivener for Mac Users: http://www.literatureandlatte.com/scrivener.html
Scrivener for Windows Users:http://www.literatureandlatte.com/scrivenerforwindows/
Good luck if you're planning to do NaNoWriMo this year.