Just checked pete's twitter and five hours ago he said "Heading to Dallas to see id (RAGE! DOOM 4!) and do some QuakeCon planning."
Your first sentence solves the dilemma here. Todd Howard is obviously in Dallas for the planning stages of QuakeCon - hell, I've heard rumors that Bethesda was planning to introduce their other games into the QuakeCon event as a way to give them all some exposure in a familiar atmosphere, so I wouldn't be surprised in the least if that's why three major players are there.
Stop being a conspiracy theorist. You're wasting everyone's time with nothing serious.