What Makes a Good Stand Up Meeting?

As an agile practitioner and consultant I have been participating in daily stand-up meetings for years now, with generally good results. Occasionally such meetings hit some speed-bumps (for example, one problem seems to be that the group of participants can become a bit too large, but splitting the group does not seem useful either). Such meetings are obviously personal and vary between teams and situations, but it was good to read an article (and comments) about effective stand-up meetings.

InfoQ: What Makes a Good Stand Up Meeting?