There's actually not a clear winner on this, its pretty split down the middle right now. It is punctuation's version of the Betamax vs VCR war.

In American English, the Oxford comma is deemed to be correct and used in most style guides except for AP. Since AP is such a huge deal over here, we still often see the extra comma omitted.

In British English, the Oxford comma is considered to be wrong and not used very much except in the Oxford style where the name comes from.

Yeah, I have multiple degrees and was never dinged for it either, but a writer friend of mine gave me no end of grief after seeing me use it.

The 2-space rule exists to prevent your sentences from running together like a couple drunk assholes....

It's incredibly annoying that the forum auto removes extra spaces.

Wow! Awesome you know what kerning is. I don't see that very often in people outside my profession.

You got it exactly right. It's only needed on typewriters because the spacing is mechanical and even. So the extra space is needed to be noticed as a stop. Not so, when the spaces between letters are optically spaced. The space can be seen. Yes optically, not mechanically. It's an art form. Scientists tend to be too mechanical. However, I do find it interesting that Steve Jobs took calligraphy in college and when he designed the Mac, their appearance of their fonts were so much better to look at.

Kerning is the removal of spaces between letters. Letterspacing is the addition of space between letters for a very wide set...but usually done as an design device.

I taught typography for a while in 2006-07. There's a book called The Mac is Not a Typewriter that applies just as much to anyone typing on a PC. There's other things like no space after a comma and a few others.

I know the history, but thanks.

It seems odd to me not to use it to me, though I know some places say not to. Commas generally indicate pauses when read aloud, and I generally say:

red (pause) white (pause) and blue

rather than

red (pause) white and blue

It's not the forum - it's all HTML.

I didn't, even know, such a thing, existed.

Only on a typewriter. When space is removed between letters, once impossible on a typewriter, it becomes unnecessary. The resultant space is enough without two.

I suspect, you don't use any kerning when you type something? If so, you use your desktop publishing like a typewriter. That's out moded.

Layout programs have this available so you can remove excessive spaces, which actually harms readability. Such things have actually been tested, as well as other typographical settings. Ad runs have even been split, showing that it deters reading of ads poorly set and other factors...as to where placed on the ad.

From there, I guess its a matter of preference. Since it is not necessary and never would have existed without typewriters, I don't like it.

To you it may look like sentences are smashed together because you are used to the extra space, but to me when I read a document typed out by someone who uses 2 spaces, the extra space just sticks out obviously to me as a wrong thing created from spastically slapping the space bar too many times.

A comma denotes a pause. The pause after Denver is the same length as the pause after Oakland; therefore, the comma belongs.

Also consider the following:

The regular characters on Gilligan's Island were: Gilligan, the Skipper, the Professor, Ginger, Mary Anne, and Mr. and Mrs Howell.

versus

The regular characters on Gilligan's Island were: Gilligan, the Skipper, the Professor, Ginger, Mary Anne and Mr. and Mrs Howell.

The Oxford comma clearly signifies that the first "and" in the sentence completes the list. When one encounters the second "and" one is already given a hint that the last item in the group is a plural item (Mr. and Mrs. Howell). Without the Oxford comma, one must read the sentence to the end and then parse out how things are grouped. The Oxford comma improves readability and therefore it is wrong to exclude it.

Mmmmm not really. The "being assholes" part that is.

Thats probably the strongest reason why the oxford comma refuses to die and has actually gained acceptance in America despite efforts to kill it.

It mimics the cadence of the words when they are spoken. Everyone pauses before the "and", so it feels right to have a comma there.

Yes, to people who like to know where sentences end, that second space is a blessing, as it reinforces the punctuation mark ending the sentence. To people who read like shit anyway, and do it basically just to get through what they're reading, comprehension be damned, it doesn't matter as much.

Yeah, it leaves this ugly gap. If you squint at the page you see a winding river of space running down the page that is ugly.