Back in the 80's and early 90's, the way you could tell if a speaker was losing the audience was through the coughing index. The louder and more frequent the coughing, the more bored was the audience. (Newspaper crinkling was another good index. The drearier the presentation, the greater the proportion of the audience doing crossword puzzles.)
Sometime in the 90's, electronics slowly supplanted the coughing index. I attribute this to the confluence of portable consumer electronics with smoking bans. Before the general social consensus coalesced around the (correct) notion that anyone whose ringtone went off in a quiet public setting was either an emergency surgeon or a colossal douchebag, it was relatively commonplace to have phones go off, and sometimes even to have people take the calls. (I remember once watching a movie in a theater with maybe a dozen people total. Some guy's cell went off, and he loudly took the call. His first line was “nothing, what are you doing?” A lesser man than I would have committed justifiable homicide.) Now it's more common for people to look embarrassed and sheepishly fumble for what seems like hours to try to turn the flippin' thing off. Why they put it where it would take them hours is beyond me, but it happens a lot.
Judging by the last several public events I've attended, the new barometer is the Crying Baby index. How long are the parents willing to let their babies shriek before finally taking them outside?
Crying babies are uniquely challenging for everyone else. It's easy to get mad at the idiot whose cell phone starts blaring “My Humps” in the middle of a solemn ceremony. But getting mad at a harried young parent just seems mean. And having been that parent, I know that there's a tension between hope that the tantrum is almost over, desire not to cave to bad behavior, and trying to estimate just how much you're annoying everybody else.
In fairness, sometimes babies enliven occasions. Nine or ten years ago TW and I saw a comedian open a public event in a gym. A baby girl started laughing loudly and randomly, presumably for reasons of her own, but her laugh was irresistible. Eventually, even the comedian started commenting on it. She got more laughs than he did, but she certainly helped the evening along.
It may be a function of the events I attend, but it seems like babies are far more common at public events than they used to be. They're fun to look at, and they have a way of brightening the moods of almost everyone around them. As a parent, they're incredibly high-risk; I shudder at the memory of administering the sniff test in public, only to find that the kid failed it. (If you haven't sniffed your kid's butt in public at least once, you aren't really a parent.) And the sheer volume of paraphernalia they require is amazing. But for the rest of us, other people's babies can be low-stress mood brighteners.
At graduation, they're everywhere, and utterly charming. Multiple generations show up together, in remarkable plumage, beaming with pride. I still melt a little every time I see a new grad in the crowd after the ceremony, hugging her kid. I got my degrees when I was young and childless, mostly out of a sense that it would be exponentially harder as a parent. As a parent now, I'm convinced that it's true. How these students get through working, studying, and parenting at the same time, I honestly don't know. But it's an honor and a hoot to watch them celebrate after the graduation ceremony. The grandparents smile, the students smile, and the babies laugh and smile because everyone else does.
Getting to watch that every single year is a perk of the job. Let the speakers worry about the crying babies during the speeches -- I like watching the laughing families afterwards. As barometers go, it's a good one.