iOS 7 may or may not be jailbreakable considering the fact that the security overhaul is COMPLETELY redone on iOS 7, meaning the exploits and delivery methods saved up may or may not work on this new iOS threshold. Until the iOS is fully released, the only possible jailbreaking will be available for the 4 since its still susceptible to LimeRa1n and is the last device to support it. If news or releases are broken out during the beta phase of the iOS, it can easily be patched with another beta release.