"Jason Johnson" <jason.johnson.081 at gmail.com> wrote in message 
news:aa22f0200710081108x48ac4b16lc83af54fcb6fefae at mail.gmail.com...
> On 10/8/07, Michael Davies <mykdavies+squeak at gmail.com> wrote:
>>
>> It's -> Its
>
> Its?  That would either be the contraction "It is" or possessive
> "It's".  So I'm guessing "It is" no longer has an apostrophe to show
> it's a contraction?

The text is "Its main advantage".

Tip: Pretend that the thing is a person and write "it" as he or his (or she 
and her)
Then "its main advantage" would be "his main advantage".

On the other hand "it's very good" would be "he's really good" i.e. "he is 
really good"

If there is an apostrophe in the "he" version, then there is also an 
apostrophe in the "it" version.
If there is no apostrophe in the "he" version then there is no apostrophe in 
the "it" version.

At least that is how I remember it.
Its [sic] easy :)

Cheers,
Andy