It depends on your habits, but it's really not as daunting a task as it would seem...1700 words a day can become stressful, but just imagine how much easier it can be if you write like crazy the first weekend and get to 10,000 words, pull back and do short bursts for a few days, rinse and repeat?
There are hundreds of methods to choose from. Again, it depends solely on your writing habits
You could even write a Sess/Kag fic, if you absolutely wanted to - I don't recall there being any rules barring fanfiction from the NaNo challenge...?
I can't wait! We can commiserate on here once things get underway...any ideas for what you'll write about?