Untethered 4.3.5 jailbreak: A few hours ago, iOS 4.3.5 was released publicly, to the surprise of many. The new update, the second of its kind in one month, is not expected to receive an untethered jailbreak anytime soon, therefore users should refrain from updating at this point in time.
Earlier today, Apple released the new iOS 4.3.5 firmware to patch a critical security issue with certificate verification in iOS. It is important to note that there is currently no untethered jailbreak solution available for both iOS 4.3.4 (which was released on 15th July) and the just released iOS 4.3.5. Do NOT update to 4.3.5 or 4.3.4 if you want to keep your untethered jailbreak.