I didn't take part this year, but I have before, four times now, and I have been a "winner" (ie. finished my novel) twice now. The first time I succeeded I had a four month old baby, the second time a 16 month old toddler, so I reckon I could do it while running around after my little one anyone can. It's just a matter of sticking to it and making time to write. Well, that and having the support of your loved ones who might cut you a little slack if your house isn't looking as tidy as usual or they don't see as much of you as they're used to.
A month is definitely an achiveable time frame, but it helps if you have a pretty good idea ahead of time what you want to write about. Editing the thing, let alone finding a market for it, takes a lot longer, but the first step is getting it written.
Nanowrimo's a lot of fun. I love the cameraderie of write-ins and races with other people taking part.
I really like NaNoWriMo, it really forces you to set goals and get the word count out even if it isn't as beautiful as it was in your mind. I find that by forcing myself to do so ends up advancing the story in interesting and unexpected ways. For the month of frantic writing, I usually end up with a year of on and off editing before it's in a state I'm happy with.