The Dev team has yet to test it, they have a strong feeling that a previously discovered exploit will help them jailbreak the iPod touch 3rd Generation. The program is expected to be called Greenpois0n, similar to Redsn0w which jailbroke the iPod touch 2G. You can the site for Greenpois0n here. This is what the Dev team wrote on their blog a few days ago:
Nobody on the team has an iPod touch 3G unit yet, but westbaer tested our exploit on his 3.1GM iPhone and it is still vulnerable :) This is a very good sign.
The dev team has also released a video showing that it does work.
Hopefully this means that the iPod touch 3G jailbreak will come much faster than it did for the iPod touch 2G a few months ago.