I identify my weaknessess and actively work on them, but I would never answer this question honestly, because I can't assume that the questioner is someone as enlightened as you.
But if they aren't, I don't really want to work for them. My being genuinely philosophical is often off-putting to people as overly smart-ass-ish or academic. I realize the dark side to this is that it limits my selection of jobs, but it makes for good conversation when I find a job I like.