John Carmack has also pitched in on the fact that id Tech 5 would only be used in-house at Bethesda, and told Gamasutra that he's happy to be out the licensing business in order to focus on finishing Rage and working on Doom 4 (and Rage 2 after that). Carmack reflected on licensing their tech in the past.
"It's interesting when you look at our technology licensing -- it was never really a business that I wanted to be in. In the very early days, people would pester us, and we'd just throw out some ridiculous terms, and we were surprised when people started taking us up on it."
He noted that while id Tech 5's megatexture direction has its uses for games like Rage, it is less suitable for things like Bethesda's The Elder Scrolls V: Skyrim where there is a whole open world to render. So while we can expect more id Tech 5 powered games coming from Bethesda, that doesn't mean the publisher is going to have all of its upcoming games run on the new engine.
id Software's Tom Willits pointed out that we shouldn't worry that becoming part of Bethesda would limit the studio's traditional openness towards its community, and that the PC version of Rage will still have the SDK and other "stuff" made available to the community. Just don't mod it into your own Just Cause game if you want people to actually be able to run it.