it's not that New Year's Resolutions are generally ineffective 'cos people end up not doing them anyway and giving up on setting them (or recycling them) for the following year. the real problem with New Year's Resolutions is the hidden perception for many of us (who set these resolutions with a great amount of zeal and genuine sincerity) that many of the things we say we will do can actually be done in a really short time.
for eg, a friend of mine says she intends to learn how to build her own desktop PC in 2003.. however, since this is something that can technically be learnt in a little over a week (or even less for the more diligent ones), the tendency is to actually leave it till 20 Dec 2003 or so before getting around to doing it (by which time other more important things would have cropped up). another example is the learning of languages or losing weight. since there is really no fixed checkpoints at which we assess our progress until the next time we set our resolutions, we end up see-sawing in our progress and may end up a little disappointed at how much we achieve in the year..
alb proposes renaming it New Year Scheduling and actually taking a whole year's calender and pencilling in exact dates of when we want certain resolutions to be done as well as progress markers along the way.
btw, here is a little something for those wondering what New Year's Resolutions to set... try this
Take the What Should Your New Year's Resolution Be? Quiz