"About 5.1 jailbreak for A5+ devices : it's not out and I have no clue when it'll happen. I'm working some hours per week on finding vulns."
"But right now we (cdev) have some pieces of a userland jailbreak, but we miss some, and even if we had them all, there's weeks of work..."
"... to put them all together in a public ready tool."
Although a jailbreak of iOS 5.1 has been demonstrated by several sources, I0n1c is the one who has demonstrated an untether. It appears he is unwilling
to release his exploit to the public.