The free iOS4 update for iPhone 3GS, iPhone 3G and iPod Touch is out, you can upgrade to the latest version by using the iTunes upgrade option. If you do not know how to upgrade to iOS4, read our earlier article on How To Upgrade to iOS4 on iPhone 3GS, iPhone 3G and iPod Touch.
Here are some screenshots of the iOS4 running on an iPod Touch 3G. One thing is for sure, there is a huge difference between the display in iPhone OS 3.1.3 and iOS4.
More screenshots will be added shortly after I have explored the new iOS4 OS.