Todd Hollenshead made the announcement at Quakecon. It gives a "competitive advantage", and is only for Bethesda published titles.
"It's going to be used within ZeniMax, so we're not going to license it to external parties," Hollenshead decreed at Quakecon 2010 in Dallas, Texas.
"It's like, look, this is a competitive advantage and we want to keep it within games we publish - not necessarily exclusively to id or id titles, but if you're going to make a game with id Tech 5 then it needs to be published by Bethesda, which I think is a fair thing."
The id veteran touched on Epic Games' Unreal Engine, saying Epic "made a strategic choice to focus on the middleware service stuff, and we never pretended to be focused on technology licensing."
"It was that we made the technology for our games, and the philosophy was that with the one team the technology was wasted if you're just using it on one game, so we wanted to be able to license it out to a small number of developers."
"Epic's made a good business out of that so kudos to them, but I wouldn't change the way we've done things." Rage is being developed with id Tech 5 and most likely so is Doom 4 given the lead time on the game's development.