Okay, they try to write 50k, which, for most genres, isn't an entire book, but it's a really good start.
In 2009 I wrote Innocent Darkness for NaNoWriMo. Which I sold, and it came out in 2012. In 2011, I wrote Charmed Vengeance and Fragile Destiny was my 2012 Camp NaNoWriMo book. So, now, I'm going to write book 4 of the Aether Chronicles series.
I probably will start a few days late, I've spent the past week and a half out of town for a family emergency so I fell behind in my pre-NaNo tasks. But I will participate.If you want to add me, I'm on the site as "sovereignqueen."
I'll also try to do daily check-in's here, so you can post your counts, commiserate, and get support.
Remember, it's only about 1666 words a day, which is actually fairly doable. I have vivid memories of writing 9k, on Thanksgiving, in 2009, while my sister-in-law's parents told me not to be disappointed if I never sold since "greater people than you have tried to write a book and failed."
Yeah, that was Innocent Darkness I was writing then.
Also, it's totally okay to "cheat" and use it as "NaNoFinMo" to finish a project or work on several projects.