I just received an email from my friend Matt Cooley with some news you can use:

Hello everyone, if you want to be able to vote in the Feb. 5th
primary here in New York your voter registration must be either
handed in Friday January 11th, or postmarked on that day. This is
also the last day if, like me, you are changing your party
affiliation from independent to Democrat to vote in the NY Democratic
primary. Make sure to check the “change party” box at the top if so.

Here’s the link:

http://www.vote.nyc.ny.us/pdf/forms/boe/voterreg/voterregenglish.pdf

Update: Postage not paid!

Hello again everyone,

A bunch of people have asked about this, and I didn’t realize it
until now myself, but if you print out the PDF there isn’t actually a
way to fold it up and mail reliably since the form says ‘do not
staple or tape’.

What I’m going to do is fill out the form and just put it in a
regular envelope and put a stamp on it.

Sorry about the confusion over ‘no postage’. The printout says it…
there just doesn’t seem to be a reliable way to take advantage of it.

Also, if you’re not sure if you’re registered, Andrew pointed me to http://www.votepoke.org where you can check your status instantly.