Folks at TiPB have tested iOS 4.2 GM on an iPhone 3G to find out if the performance is better.
Screenshots Of PwnageTool & Sn0wbreeze To Jailbreak iOS 4.1 Reveals Support For All iOS Devices; Release Imminent
PwnageTool and Sn0wbreeze will allow users who want to jailbreak and also unlock their iPhone to update their iPhone with a pre-jailbroken iOS 4.1 firmware while preserving the baseband so that it can be unlocked using Ultrasn0w.
In this guide, we will take you through the step by step procedure to jailbreak iOS 4.1 for iPhone 3G.
They have just released the beta version of Redsn0w 0.9.6b1 for Windows users as well.
It uses the pwnage2 DFU-mode exploit and not the SHAtter exploit that was discovered by pod2g so it can be used to jailbreak only iPhone 3G and iPod Touch 2G.
Sn0wbreeze To Jailbreak iOS 4.1 For iPhone 3GS, iPhone 3G, iPod Touch 3G, iPod Touch 2G For Windows Users Released
Sn0wbreeze allows users to create custom iOS 4.1 firmware so that they can update and jailbreak their iPhone and iPod Touch with iOS 4.1.