I don't think I'm going to make any New Year's resolutions. Of course, it sounds like fun—who can resist the allure of planning for a better life?—but the problem I had last year is that my resolutions became obsolete before the year was up.
For example, it seemed like a terrific idea to do a year without sugar—until the moment in May when I was sitting in a five-star restaurant in Maui and was presented with a palate-cleansing bowl of fresh sorbet between courses. In other words, my future self had new information that my past self had not anticipated when making the resolution (the new information was "It's better to have a tiny bit of sugar than to be annoying in an extremely fancy restaurant"). Later on, I decided that avoiding sugar wasn't nearly as important to me as avoiding gluten, so I ditched that resolution altogether. I also "cheated" on my resolution to stay off the scale. Sometime in the summer, I felt like I was in absolutely terrific shape and perhaps close to an ideal weight, and I wanted to see what it was (it was 160) in order to have a reference point.
Anyway, my logic is that my future self will, by definition, know more than my present self, and I might as well just trust her to make good decisions on our behalf. My future self hates being bossed around by someone with incomplete data.