Since I have the 2 versions ago... the new version will not read those... nor write to any of the older versions, period. So if you *DO* open the file from "last version" and save... can only be opened by the new version since there is no option to "save as" an older version.
They probably justify this as: Mavericks is free and includes newer versions for previous installations
I don't know if the new versions of "iWorks" pages/numbers/etc are free for machines unable to run Mavericks. As I never checked before I updated to Mavericks.
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After some checking... the answer is *NO*... you have to be running Mavericks to get the newest stuff. http://www.apple.com/mac/pages/ at the bottom goes to: http://www.apple.com...s/mac/up-to-date/ and apparently, if you've ever installed/purchased them before (like I did from DVD) you are eligible once on Mavericks. I also believe the "dates" are bogus, as I updated well after those dates.
Kind of a crappy thing to me. But hey, what ever works.
The other thing they have done, is change the interface to make it similar to the iPad/etc versions. But since the wife likes the new version better... it is fine with me as I use LibreOffice for everything.
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After plunking around... it will not *SAVE* the originaly odcs in the old format, but will "Export To" PDF, Word, Plain text, ePub and Pages '09...
This means it SUCKS... then you have to have 2 or 3 or more versions of the same doc floating around. Meh.