iPhone 3.0 Jailbreak 0
“About 5 hours ago (Thursday evening, less than a week after the 3GS
launch), we were able to verify that the 24Kpwn exploit that the hybrid
team used on the iPod Touch 2G is still applicable to the bootrom of
the iPhone 3GS. That means we can use the same sort of technique used
by our current redsn0w tool to jailbreak and unlock the iPhone 3GS.” iPhone Dev – Team Blog
So apparently you can jailbreak and or unlock your iPhone 3.0 3Gs. Because some of the fundamental flaws that allow this crack still remain in the new phones.
Read a little bit more about it here.