This is my fourth NaNoWriMo, which I think gives me enough experience to muse about how different they've all been for me.
The first year I signed up, it was an abject failure because that was The November Everything Happened — my grandmother died, my 17-year-old cat died, and I lost my job all within two weeks. I got through the funeral, the last trip to the vet's, and finding a new job as well as one could be expected (was only unemployed for two weeks, all told), but that didn't leave me with enough energy to write a novel, much less in the remaining days of November.
Two years ago I joined with a bunch of other people who were in the writing group I belonged to at the time. As it turns out, only myself and one other person completed. I was surprised, because there were a number of very strong writers in the group who had signed up, and they didn't finish. It was a good lesson in quality versus quantity, but at the same time it made me want to finish again next year. I have to admit that I didn't use entirely new material per the rules that year. Instead, I wrote fifty thousand new words on a story that already had about seven thousand words done on it. I justified this by not claiming the completion certificate, which according to the NaNoRebel forum is an acceptable thing to do.
Last year I was back, this time with a story that didn't get started until 1 November. I wrote the entire thing in eighteen days of the thirty available, which meant lots of marathon sessions and a photo finish on 30 November (which made me late for a craft event at a friend's but was so worth it! Luckily the ever-chaotic Tara was understanding.)
I tried editing the novel I wrote for NaNo 2008 in the spring, and discovered it needs a lot more than editing — more like a full rewrite. Maybe someday. Right now I want to push ahead with new ideas.
This year I have one five-day weekend and two three-day weekends in November, thanks to a stricter take-your-vacation-or-else policy at work. I'm also creating a phase draft for this year's NaNoWriMo novel, thanks to Lazette Gifford via Johanna Harness. What this means is that instead of pulling away as quickly as I can towards the 30 November goal of fifty thousand words, I've written just over a thousand words just to put myself on the chart, and now have retired to writing the rest of my phase draft. I know the ideal would have been to get the phase draft done before November started (um, next year?), but this is how things worked out. I did use the phase draft as I had it so far to write my first thousand words, and it did make things much easier. At least I have those vacation days to put in some marathons and get caught up.