I have used both the direct link decided by software finder, i have dowloaded directly from the link http://support.apple.com/kb/dl1421.
it keeps telling me that the file is corrupted, or failed checksum. i even skipped the check and it still crashed the installation.
i have many hundreds of hours work on adobe illustrator and other programs now rendered useless by this upgrade.
i have a late 2010 macbook air, 1.6GB, 4GB RAM
I have no issues with that file, so I would assume you have a corrupted download. Try again. You may want to investigate why your downloads are being corrupted.
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