You may have seen a couple of articles floating around the web encouraging writers not to 'Nanowrimo'. Reasons include: 'If you are a serious writer, you would just write anyway', or 'only non-serious writers would participate', or 'expect to write a crappy story in 30 days'.
I'm of the mind-frame that if this is what will motivate you to write, then do it. I know that life gets busy; I certainly struggle at times to find a moment to write between juggling the kids, the household, my job, and my writing clients. Sometimes, we need a group of writers to encourage us and a challenge to motivate us. There is absolutely nothing wrong with this.
However, as Nanowrimo closes in, keep the following in mind:
Your Nano novel will not be ready for publication by December 1. Your novel needs to go through numerous drafts before you self-publish, or send it to a publisher/agent. It needs to be put away for a month, maybe two, and then looked at with fresh eyes.... and then re-written again. If you want to be lauded for your work, then take the time to make it exceptional.
Keep on writing!