(adsbygoogle = window.adsbygoogle || []).push({}); Whenever you go to Settings-> System Update-> Update via Internet your PS3 searches an unknown location to download the update.

Well the location it goes to is:
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If you go to that website, you can use it to download the firmware to a USB drive.

You can also go to "You must login or register to view this content." to see the current firmware number. It is also where to find the direct link to the update.
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If you aren't from the US you can substitute both "us"'s in the above link with the following:
"au" for Australia
"be" for Belgium
"cn" for China
"eu" for Europe
"jp" for Japan
"kr" for Korea
"mx" for Mexico
"nl" for Netherlands
"ru" for Russia
"sa" for South Africa
"tw" for Taiwan
"uk" for United Kingdom

For Demonstration PS3s, they go to "You must login or register to view this content." for their updates.
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