NaNoWriMo was a great thing for me, because it showed me that I could finish a novel in 30 days. The timing has worked out for three of my novels that I was ready to begin writing on November 1st, but this year I'm afraid it's a different story. I won't be able to complete NaNoWriMo this year.
I have my reasons, but for now I'm keeping them a secret.
Regardless, if YOU are going to Go NaNo this year, best of luck! Don't stop writing, and remember that it's only 1,667 words a day to get to your goal! That's just a couple of emails, if you're long winded, or one long raving tirade to an ex-lover. And if you reach 1,667 words in one day and have some more time, keep going! Don't let a number stop you from getting ahead. My goal two years in a row was to reach 100,000 words (I failed, miserably, and engaged in self-loathing for months afterward) but it made 50,000 seem like a (very over-described and expository-prose-heavy) walk in the park.