According to i0n1c, a well-known member of the iOS jailbreaking community, users should not expect to see an untethered jailbreak for the just-released iOS 4.3.4 anytime soon.
JailbreakMe 3.0, released a few weeks ago, is an easy jailbreaking tool that takes advantage of a PDF exploit in Mobile Safari. Unlike other tools that require a computer connection and a moderate amount of skills, JailbreakMe simply requires users to point their browsers to JailbreakMe.com: within minutes, any iPod touch, iPhone and iPad, including the iPad 2, will be unlocked. If you’re planning to jailbreak your device using JailbreakMe 3.0, check out our write-up.
Even if a new untethered vulnerability is found in iOS 4.3.4, it might be unwise to exploit it just yet, since Apple might then patch in the upcoming iOS 5. Instead, it would be smarter if the developers kept their findings secret in order to come out with a jailbreak for the next iOS quickly. For now, you can jailbreak iOS 4.3.4 using Redsn0w, or PwnageTool (iPhone, iPad, iPod touch), although it’s not an untethered solution, which means that you’ll have to plug your devic