If someone walked up to you and told you that yellowsn0w just became ultrasn0w, you would likely look at them funny, and walk away, disgusted. However, for the iPhone jailbreak community, the fact that Yellowsn0w just became Ultrasn0w might be the greatest thing that ever happened.
The (in)famous iPhone dev team, who was responsible for the original jailbreak as well as keeping up with Apple's constant stream of software updates, and jailbreaking those as well, has released a video that shows the ultrasn0w software unlocking an iPhone to work on any GSM carrier. This hack should work with any iPhone available.
Due to the fact that the firmware leaked earlier than the official release date, the dev team was able to finish their hack by the time 3.0 was released today. Of course, Apple has proven that they frown upon all iPhone hacking, most likely due to their GINORMOUSLY lucrative deal with AT&T, so they will probably patch this one soon enough.
However, for the time being, we suppose it must be exciting to both copy and paste AND use T-Mobile on an iPhone. The hack is set to release Friday, so if you are into that sort of thing, you can probably find it in time for the 3G S release. Meanwhile, they are still testing new versios of QuickPwn and the PwnageTool, so the official jailbreak (which will let you use unapproved software on your iPhone) should be imminent as well.