Only a few weeks after the 4.3.1 untether created by @i0n1c was released, Apple pushed out firmware 4.3.2. Thankfully, it appears Apple didn’t have a chance to fix the hole used by @i0n1c’s untether, so he ported his code over to 4.3.2’s kernel. Today’s redsn0w has been updated to include it.
The 4.3.2 untether works on all devices that actually support 4.3.2 except for the iPad2: