NaNoWriMo?

So, I'm having some trouble picking a topic, and it just so happens the start is three days passed. I have two at the moment:

1. A typical zombie survival story (this is sort of a fallback)
Reasons to do it:
- lots of character development
- descriptions come easy
- kinda easy to make not cliched
- lots to work with
- don't have to do much research because I have already written some zombie related stories

Reasons not to do it:
- has been run into the ground
- very dark

2. An original dark fantasy story
Reasons to do it:
- would be more interesting
- don't have to do ANY research because its all made up
- I get to use swords ( I like them better than guns)
- I can make it... crazy, and different and not at all like real life, which is sorta the point right?

Reasons not to do it:
- Has been run into the ground
- Cliches are everywhere
- Must be very creative to come up with something new
- lacking in plot

So, what would you guys do? I guess this could also serve as a what you are doing your NaNoWriMo on.

Option two, the dark fantasy story. It sounds far more interesting and less over-done than the zombie story.

Do the more interesting one! Take a risk! It's NaNoWriMo! You can afford to do something daring!

One of your reasons for doing the dark fantasy is being able to use swords, right?
There's no reason not to be able to do this wth the zombie idea. After all, you've mentioned that finding a unique idea for a zombie story would be hard, that's a pretty big change from the traditional zombie story.

My personal decision would be taking up the zombie idea, and giving it a unique flair that sets it apart from the rest of the genre.

Good luck whatever you choose.

Er, how are you going to develop the zombies' character?