According to http://dictionary.reference.com/search?q=it's :
What’s the deal? Am I missing something here?
Thanks!
P.S. I tried doing a search on this subject, but as you can imagine, I had no luck.
It’s is used as the contraction of “it is”.
D’oh! I see what you’re asking.
I think your source is wrong.
No, the reason it’s a bit non-intuitive is because “it’s” is the contraction of “it is.” That’s why the posessive form of “it” has no apostrophe, so they don’t get confused.
The answer to your question is “no”. Not sure what’s confusing you, though.
“Its” is possessive. “The dog wagged its tail.” This is different than any other possessive use of the “s” ending in English AFAIK, in that it does not use an apostrophe. Dunno why. “The cat scratched the dog’s tail” is the usual way to write a possessive.
“It’s” is a contraction for “it is”. “I hope it’s going to be sunny today.”
The uses are not interchangeable.
Oh, I’m aware of the difference between “its” and “it’s”…That’s why I’m confused about that link.
It shows a definition of “it’s” as the possessive of “it”.
I’m just wondering if maybe I misread the site or something.
Guess I shoulda clarified.
Oh, sorry, now I see–yes, I think the source is mistaken or being excessively descriptive, I have never seen this waffling from an authoritative source.
Some sources are prescriptive, meaning they presume to know what’s right and tell you so with authority. Some are descriptive, meaning that they just document how people actually talk without drawing a judgement about correctness.
Anyway, I think the online cite is just plain wrong. My 1981 Webster’s on my desk has the definitions everyone has been describing.
OK, the same source says this:
its ( P ) Pronunciation Key (ts)
adj. The possessive form of it.
Used as a modifier before a noun: The airline canceled its early flight to New York.
[Alteration of it’s : it + -'s.]
Usage Note: Its is the possessive form of the pronoun it and is correctly written without an apostrophe. It should not be confused with the contraction it’s (for it is or it has), which should always have an apostrophe.
Read the entire definition
[Alteration of it’s : it + -'s.]
Usage Note: Its is the possessive form of the pronoun it and is correctly written without an apostrophe. It should not be confused with the contraction it’s (for it is or it has), which should always have an apostrophe.
The reference is simply that its = it’s exists, not that it is a correct usage. Like the word “ain’t.”
That’s not quite correct. The possessive “its” has no apostrophe because it belongs to the class of possessive pronouns:
mine
yours
his
hers
its
ours
theirs
whose
. . . none of which takes an apostrophe.
Remember your possessive pronouns! They are a special group all their own, with different rules from the possessives of common nouns.
The confusion arises from, I assume, either a misdirected link or an oddity in the search function at dictionary.com. Note that the entry for “its” is identical to the entry for “it’s”. The former is the correct page.
Note that “it’s” can be “it is” or “it has” (e.g., it’s been a good day).
Scarlett67 makes a very important point. Pronouns are a special case, and never use an apostrophe for the possessive. If you don’t normally write “hi’s,” her’s," “our’s,” “your’s,” or “their’s,” there’s no reason to think you should write “it’s” for the possessive of “it.” (If you do normally write those forms, you have a bigger problem.) Of course, the fact that the word “it’s” does exist (where those others I listed do not) can lead to confusion. Think carefully about whether you’re saying “it is,” “it has,” or “belonging to it” to help you choose the correct word.
Except “one’s” 
I think zut nailed it. Note how the it’s in the “it’s” search result page is replaced by the “its” in the “its” search result page, keeping the definition the same.
Maybe the heading it’s on the search page for the definition in question is somehow [incorrectly] dynamically created from the search term “it’s” itself.
I checked a few of the online Websters dictionaries, and they do not have an entry for it’s.
So, the search engine gave back the definition for its instead.
Awl is write with the whirled.
Peas.
I checked a few of the online Websters dictionaries, and they do not have an entry for it’s.
So, the search engine gave back the definition for its instead.
Awl is write with the whirled.
Peas.
Next we will see hi’s. Anyway, it’s only a question of orthography, not actual speech.
The only time “it’s” is correctly used as a possessive is when it is used as a direct noun or proper noun rather than a pronoun, as in: “Gomez and Morticia enjoyed Cousin It’s visit.” or “It’s place in the dictionary comes between issue and item.”