Download iOS 4.1 Final Version for iPhone 4, 3GS, 3G, iPod touch
Apple has just released the very final version for iOS 4.1 for iPhone 4, iPhone 3GS, iPhone 3G and iPod touches. This version of iOS brings a number of new features for iPhone and iPod touch users including: Game Center, HDR Photography for iPhone 4, iTunes Ping, HD video upload on YouTube and MobileMe for iPhone 4 and iPod touch 4G and so on. If you want to keep your jailbreak and unlock, you better not update to this latest firmware now until and unless new jailbreak and unlock tools are available for download.
To update to iOS 4.1, all you need to do is to connect your iPhone or iPod touch with your computer via USB and start iTunes. You should now see a message as shown below. Simply click on “Download and Install” button to get on to the new firmware.
Direct Download Links for iOS 4.1 (Official from Apple)