I'm sure this has been discussed and debated to death by now, but I thought I'd throw in my two cents after using my Droid for a few days.
At first the unlocking pattern utility is really cool ... but the smudges left behind might make it easy for someone to guess what pattern you are drawing. I find myself trying to determine what patterns would best account for my oily fingers. A better implementation would have the dots spaced with random variations/distortions. For example, the dots could be uniformly stretched out or contracted, non-uniformly stretched/contracted (ex: one side a la trapezoid), or the entire grid could vary in its orientation or placement. All of this of course would be random. As it exists, I personally would rather have the traditional pin/ keypad.
