There may not be many hardware changes inside the PS3 Slim, but each new console will ship with the PlayStation 3 3.00 firmware update. Here's what you can expect:
There are a few minor cosmetic changes to the interface and XMB (cross-media bar). Most noteworthy is a new tab under the PlayStation Network icon called "What's New." It will highlight new featured downloadable content, news, etc., and will also be the first thing you see when powering on your PS3.
Firmware 3.00 will also introduce new dynamic theme support. These are much more involved than previous PS3 themes, with fully animated backgrounds and even the ability to change themes as the day goes on.
A status box in the upper right corner will give you a heads-up display of how many friends are online and your current message count. Below it, a ticker shows Sony news and information.
Fans of avatars are in good shape, with 3.00 introducing a brand new batch of selectable icons. There will also be "premium" avatars available for purchase in the PlayStation Store. Lastly, trophy support will now be distinguishable between base and add-ons so you can compare your progress among the two.
Sony plans to release firmware 3.00 soon and it will be available on every hardware version of the PlayStation 3.