Early reports note that the TaiG jailbreak utility doesn't work with iOS 8.1.2; however, that's to be expected as there are values that would need to be changed for the new firmware.
The first clue that the jailbreak may not have been patched is that the kernel of iOS 8.1.1 and iOS 8.1.2 have the same version number.
@iAdam1n: Well it seems that the kernel exploit used in TaiG for iOS 8.1.1 is not patched as the kernel version is the same on 8.1.2 as 8.1.1.
The second clue comes from Apple itself via iH8Sn0w.
Not sure if this was already said... But judging by http://support.apple.com/en-us/HT6598, 8.1.2 should still be vulnerable to taig jb.
When examining the support document detailing the security content of iOS 8.1.2 there is no mention of any exploits closed that would break the jailbreak.
To be safe, if you were late in jailbreaking iOS 8.1.1 we suggest you update using iTunes while the signing window is still open, then visit the iClarified Jailbreak Wizard for instructions on how to jailbreak. If you have already jailbroken, take care not to update to iOS 8.1.2 until a jailbreak is 100% confirmed.
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