Dev Team member cpich3g tweeted the following info earlier today:
3gs 3.0 pwned->3.1 pwned. Props to Musclenerd, Wizdaz and thanks Bumble-Bee & ToddJG for testing. tinyurl.com/y8sr4p3 tinyurl.com/y8z277l
Both the links available in the Tweet takes to the screenshot displayed below which shows iPhone 3GS running OS 3.1 have the same old baseband version 04.26.08. Which means using the method used by the dev-team, users will be able to unlock iPhone 3gs using the same UltraSn0w.
So we are a step closer to having our hands on to PwnageTool update or any other new tool coming from the house of the Dev-Team to safely update our iPhone 3GS to OS 3.1 and then jailbreak & Unlock it.
Lets wait for the Dev-Team announcement on their official blog to jailbreak iPhone 3GS OS 3.1. We will keep you posted as there comes any update. So, stay tuned at iphoneheat.com.