I found the article The Philosophy of Punctuation via Daypop. It's fun. A couple of thoughts:

Great opening: 'Punctuation absorbs more of my thought than seems healthy for a man who pretends to be well adjusted.'

Like Robinson and Strunk, as you may have noticed, I use a comma in a series even when it directly precedes the 'and'. I noticed my last time through 'The Lord of the Rings' that Tolkien does, too, and I probably got it from him. I've noticed this tendency more in British prose than American.

I'm much more of a Platonist in punctuation. I generally tend to try to write in good spoken English. To put it another way, I'm more of a descriptive linguist than a prescriptive one.

I almost never use semicolons anymore, unless to set off a series that includes commas in its separate items. Better just to stick to periods. I'm like Robinson in this regard.

If it's on Daypop, it's usually on MetaFilter. There's some discussion of the same article over there.