I always hand-write. For me, its faster and I can easily format it however I like.
That.
For a few reasons:
1. It's the holidays. You have time anyway.

2. The formatting thing is so true! The time you gain by typing everything up is usually lost in grappling with the formatting.
3. You do retain the information more.
4. Because writing requires more effort, when I handwrite notes I generally only write stuff that's really important, or stuff I would constantly refer back to. And when you type, you run the risk of just including everything, which may render the notes useless in the end. (I wouldn't want to read through pages and pages of typed notes to find, say, one formula, or one date).
Moderator action: removed real name, sorry for the inconvenience