How hard can a hat be?

I just recently re-discovered and started working scarf number (probably) 8.5 or so... basic pattern of knit 2 purl 2 (cast on 40 stitches).  I think I started this scarf right after I moved to NYC in June 2005, if not even earlier.  The big goal is to finish it by New Years (it has gone from less than 1 needle length to about 4 lengths now).  I'm fine if it takes another week past New Years, as long as I finish it in time to wear it while it is still winter.

Not that I'm hoping for the cold weather to last any longer... but after this scarf we're going for a hat.