According to a series of tweets by p0sixninja and MyGreatFest, there is a possibility that an iPhone 5 jailbreak will be demonstrated live at My Great Fest 2011. The iPad 2 jailbreak is currently under development, but the overall progress is unknown—whether or not a bootrom exploit exists is still a mystery. If comex is able to develop a bootrom exploit, the same technique will work on the similarly spec’d iPhone 5.
The event starts September 17th, so if (and this cannot be stressed enough) an iPhone 5 is released sometime in August or early September, it is “highly likely” that a jailbreak will be ready in time—but certainly not guaranteed. Other jailbreak developers, like MuscleNerd, have reservations about this, and are very hesitant to give an ETA (you can check out some bickering on Twitter).
My Great Fest is the first convention centered around jailbreaking and the iCommunity, and will be hosted in London. Admission tickets start at £27.