I think you’re all a bunch of nut’s!
I am aware of this. My point was that is the only context in which that apostrophisation would be correct is if it were possessive.
Check the OP again, hammos1, we’re talking about apostrophes. So although SmackFu reply to your post was wrong jjimm’s wasn’t.
To be fair, I expect people to sometimes get it wrong with possessives of words ending in ‘s’, or describing something belonging to many of the word “potato’s.”
What is ridiculous is not to know that typically plurals DO NOT take apostrophes and possessives DO. Also, remember that if you forget an apostrophe, or make a mistake with an unusual construct, you appear to have made a mistake. If you add an apostrophe you appear a FREAKING, GIBBERING AMOEBA!
OTOH, maybe it would make sense to use apostrophe’s in plurals to indicate what the original word is.
PS. Aren’t you afraid that someone out there is writing pen’ii?
Hey, everton - thanks for the spirited defense, and sorry to point out that there should be an apostrophe-s in your post after SmackFu. 
Long live Gaudere!
To be honest, I think it is this practice that causes all the confusion.
I am a bit surprised that there have been this many replies without someone mentioning Dave Barry who, as “Mr. Language Person” and elsewhere, has written extensively on the proper use of the apostrophe and its cousin, the quotation mark(s?) I can’t provide an on-line link but I’m sure it is in one of his books.
“Thank’s” and “Your welcome!”
On the other hand, the proper way to form the plural of a numeral, letter, or symbol referred to as itself is with a “'s”, such as “T’s, 8’s, and @'s”
For example, “JohnT’s use of F’s in the last paragraph of his post above were an attempt at euphemizing gratuitous obscenity in a GQ post.” 
This annoys me also. People basically half remember what they know about grammer, and apply it liberally. I’m not much on grammer, as you may note from my posts. I understand the basic rules, like where apostrophies go, but get lost in when to italicize or bold article and book names, and have a tremendous problem with run on sentences as I tend to ramble on and on with no end in sight.
The most annoying sign I have ever seen:
I was in 10th grade. A contender for Validictorian of my class made a sign for Mr. Hayes that said “Mr. Hayes’ Class” I used to shudder everytime I walked by this sign.
Grammer is being taught just like everything was taught in my High School. You learn something long enough to pass a test, then forget it. You review for the final, then forget everthing. I was taught the same thing over so many times, I dropped out to same me anymore pointless timewasting.
Eh… I don’t know about that. It is more acceptable to use an aprostophe in that manner, but I certainly wouldn’t consider something like “1980s” improper. It’s really more a matter of style than it is of grammar, so one style guide may tell you to use them in this case, and others may not. The previously refered to Apostrophe Protection Society claims that “1000’s of bargains here!… should read 1000s of bargains here!”. But, on the other hand, you can find an entry in a dictionary like this:
In my opinion, I agree with the Preservation Society that the truly proper way (or, at least, the traditional way) is not to use the apostrophe to make a plural in these cases. The only time where that is confusing is for lower case letters. But using apostrophes to form the plurals of numbers and such has become so common that trying to correct it is as futile as Canute and the tide.
The blatant sucking up by this Valedictorian candidate must have been really annoying, since there’s nothing wrong with the apostrophe on the sign. Some would argue that it should be “Hayes’s”, though.
PS It should be potatoe’s, everyone. Keep it straight.
What’s wrong with “Mr. Hayes’ class”? It is his class and therefore the use of an apostrophe is correct. Another option would be “Mr. Hayes’s class,” but the double “s” looks a little clunky.
According to the styleguides I’ve read, there isn’t a proper or improper way of doing this. It’s a question of style, and I personally think the plural of a letter or number shouldn’t be separated by an apostrophe, just to avoid confusion: thus Fs and 3s and the 1900s could be seen as ‘proper’.
According to my copy of Fowler’s, a trailing apostrophe should only be used when the last syllable begins and ends in an S. Thus Hayes’s is correct, as is Jesus’.
“According to my copy of Fowler’s, a trailing apostrophe should only be used when the last syllable begins and ends in an S. Thus Hayes’s is correct, as is Jesus’.”
See? Crazy rules!!! 
Even the SDMB Grammarians are arguing it out, which is why we need Apostrophe Reform™ now!
Thanks, Polycarp. 
Btw, just because I don’t remember the rules doesn’t mean I don’t care. Apostrophe usage is just one of those things I rarely get right. We all have our weaknesses, those things just happen to be one of mine.
“potato’s”. Apostrophe used in a contraction sense because of the replacement of the ‘e’ of potatoes. Which is a plural.
Why are you contracting it? It’s not like a Shakespearean contraction, e.g. “lov’d” (which used to be pronounced “lovéd”), because it isn’t removing a syllable.
“Potato’s” as a contraction of “potatoes” is surely simply incorrect. Unless you can show me otherwise.
You’re right, jjim, “Mr. Hayes’s” is correct, not “Mr. Hayes’”. Interestingly enough, however, Strunk & White’s exception to the rule of " 's " differs from Fowler’s. According to Strunk,
http://www.bartleby.com/141/strunk.html#1
You know, there’s a lot of things out there that I don’t understand, but up until now I thought that I had at least nailed the apostrophe!
Julia,
It’s refreshing to see someone else who’s appalled at the severe downgrade in grammar. I was never a nut about English when I was in school, but I did notice that proper speaking and writing did distinguish oneself from others in a positive manner. Not that my intention was ever to be a condesending sort of person. But I’ve prided myself on being a literate person. I am shocked at some of the terrible misspellings and misuse or non-use of punctuation, particularly by people I wouldn’t expect it from. I feel as though this lax attitude by the general populous in regard to the English language is unfortunately an indication of our decline as a leading nation; history repeating itself, i.e. “The Decline of the Roman Empire”. I hope I’m wrong, but I wouldn’t bet on it.
Best regards,
Jake
My favorite sig ever on a Usenet post was something along the lines of “Contrary to popular belief, the apostrophe does not mean ‘look out, here comes an S!’”
There is one–and only one–place that I would use an apostrophe for a plural and that is for the plural of an acronym written (for whatever reason) in lower case. Something like, “There were too many url’s to remember”. I would prefer, “There were too many URLs…”, though. But contrast that with, “The computer ran at 400 mips (million instructions per second)” in which the “s” is not a plural.
There are restaurants I have been to that ought to say: We serve “food”. But that is another rant.
And I don’t know any rules for using apostrophe. You use it for a contraction, for a possessive noun (not pronoun!) and nowhere else, with the possible exception of the first paragraph of this post.