Today the iPhone launches in Europe and we already reported a couple days ago that European iPhones ship with the new iPhone firmware 1.1.2.

Today it is also expected that the new firmware 1.1.2 will roll out via iTunes to all iPhones in the United States.
Engadget got a link to download the 160MB iPhone firmware 1.1.2 already from the Apple support site and made the first tests.
The Apple firmware 1.1.2 is not accompanied by any documentation or release notes at this time.

As already mentioned in the first report about the 1.1.2 firmware the TIFF jailbreak exploit is not working anymore. Apparently the update makes the iPhone perform faster, but no new features are found. For Europe the firmware 1.1.2 added multilingual support including localized keyboard layouts.
More details on Engadget.