Pwn20wnd has announced that switching to the new Cydia Substrate from saurik will bring stability and battery life improvements for those using the unc0ver jailbreak.
P0sixninja has revealed that he will not be using his jailbreak exploits to release a jailbreak for iOS 6.1.3; rather, he will be holding them back for iOS 7 or iOS 7.1.
Instructions on how to jailbreak and unlock your iPhone 3G on the iOS 4.2.1 firmware using RedSn0w for Mac. This tutorial can update your baseband if needed for unlock.
The iPhone Dev-Team has announced RedSn0w 0.9.15b1 which brings numerous new features including the ability to restore to older firmware not being signed by Apple.