MuscleNerd has tweeted that the iPhone 4 has been jailbroken by comex! This particular exploit can be easily patched by Apple, so it’s unlikely (but possible) that the Dev-Team will release it; but nevertheless, it is a nice step towards a full jailbreak for the new iPhone.
Update: p0sixninja has confirmed via twitter that the new Spirit (with the Dev-Team version of this exploit, without using Apple software) will be released July 2nd. [Thanks -lkv-] There is no official release date. Talk on the dark recesses of the interwebs of July 2nd are incorrect and are misinterpreting tweets. The Dev-Team’s musclenerd has said comex’s new userland jailbreak is nowehere near being finished and, as with all jailbreaks, there is no official release date.