John Carmack via twitter
"Since the question keeps getting asked -- no, I am not going to be at Quakecon this year. My 2.5 hr talk at SMU should still be released."

The talk at the Southern Methodist University took place on April 25th and has not yet been published (people.smu).

John had tweeted several times in the past he would keep his keyspeech aka techtalk at QuakeCon if Zenimax even let him. But recently Zenimax sued John for a Virtual Reality code copy (bluesnews ZeniMax vs. Oculus, Oculus responds). Who knows, if it had not been for the current action he might have gone to QuakeCon.