The idea for Nanowrimo was originally based on a comic concept where writers would create one short comic strip in one day. _One day_. This allowed for creativity.
IMO 30 days of it is not good for creativity. It becomes a mind-numbing grind that produces very little prose of value. I'm doing okay because I'm working to a very fixed outline and I'm inserting preexisting texts as well as writing fresh material, so I'm 'cheating' and I won't be entering a final count to become a 'winner.' Actually I'm kinda behind now because of other responsibilities. So far it has been a positive experience for me because I'm using it sensibly.
Sorry no one else is doing something with it (whatever word count they think is valid for them). I think it's fine to say that one will do 500 words a day. Then it becomes a useful tool.