MacRumors has discovered that iPhone's firmware has evidence of the next generation iPhone which has been designated "iPhone2,1". This new model number can be found in the USBDeviceConfiguration.plist in an unencrypted firmware.
Apple uses these models numbers to distinguish between different hardware models. The original iPhone carries the model number of "iPhone 1,1" while the 3G iPhone is labeled "iPhone 1,2". These numbers do not change for simple storage increases and instead represent functionally different devices. Similarly, the iPod Touch was originally introduced as the "iPod 1,1" and the most recent hardware revision was labeled "iPod2,1".
Meanwhile, at least one developer has noticed actual "iPhone2,1" models in use based on PinchMedia ad serving reports.
Apple has just pushed out Firmware 2.2.1 for iPhone and iPhone 3G, iPod touch, iPod touch 2G. You can download them here. Firmware 2.2.1 cannot be jailbroken at this time, so unofficial application users should wait for new version of QuickPwn from DevTeam. Unlock (yellowsn0w) also doesn't work for 2.2.1.
This update contains bug fixes and improvements:
Version 2.2.1 (Build 5H11)
Modem Firmware 02.30.03
Improved general stability of Safari
Fixed issue where some images saved from Mail do not display correctly in the Camera Roll
Fixed issue that caused some Apple Lossless (ALAC) to skip during playback
Unofficially Apple fixed SMS bug: users suddenly experience inability to send SMS text messages on the iPhone 3G, receiving the message "error sending" upon attempting to send.