The latest version of the blackra1n jailbreak has hit the streets. RC2 will even jailbreak brand new iPhone 3GS models running 3.1.2 from the factory with a "tethered jailbreak."
This means when restarting your jailbroken iPhone the device must remain connected to your computer to properly boot. Apple thwarted the “24kpwn” exploit used by Geohot and iPhone Dev-Team in the latest firmware release on new iPhone 3GS models, making the tethered jailbreak method necessary.
Of course, Dev-Team is working on a new version of PwnageTool that will also include the tethered functionality. In the meantime, users who need it can download blackra1n from blackra1n.com.
According to Geohot, the new release has these features:- Fixed 3G issues
- Tethered jailbreak for factory-fresh iPhone 3GS’s and new out-of-the-box iPod Touch 8GB
- Fixed Icy issues
- Both Windows and Mac
If your iPhone is already jailbroken with blackra1n RC1 there's no reason for you to redo the process with RC2. Dev-Team's PwnageTool 3.1.4 will not jailbreak new iPhone 3GS devices that come pre-installed with firmware 3.1.2.