You're right that round manhole covers can't fall through, and that's a big reason. Another primary reason that I've heard is - the dang things are heavy! One person can roll a round manhole cover, but of course that wouldn't work with any other shape.
And of course, the "creative" answer: Manhole covers are round because maholes are round.
Well, I've never been to Channel 9 before, and I came to watch this video, if that's a useable data point. Not a developer, but I am in IT - I'm a Systems Analyst.
I'd watch it again, it seemed interesting. Thought the rock-n-roll transitions were a bit frenetic, but whatever. I'd think there'd be an audience for this kind of show, covering topics of interest to developers that aren't necessarily code-related. Get
some folks on - the "people behind the code" that folks keep talking about, get their snippets of input on each of the topics, instead of it being all Laura and Max all the time.
The comments on here are hilarious. I GET that you're all developers. Does that mean you don't talk about anything other than code? I think the intent here is to cover the kind of topics you're probably talking about at the watercooler that week...but some
of these folks seem to be shouting "NO! If it's not code related, you're wasting my time! I'm not programmed for social interaction of any kind!" Sheesh.