I don't want to bag out on id.. but the games they've done in the past that qualified as FUN - the basic premise was to just kill wave after wave of bad guy/demon/robot type soldier guy. Their games have never been very "deep", but they have been fun to play. This looks to me like they felt a bioware style game was more appropriate but have none of the bioware talent for making engaging story/dialogue.
I'm sure I read somewhere that id were no longer going to be in the game of tech licensing, but I could just be mistaken.
It's my impression that they're holding out on open sourcing id Tech 4 until after the release of Rage, so it would make sense that they still intend on licensing id Tech 5.
The story tomorrow isn't going to be the bad reviews, it's going to be the fact that almost nobody seems to be able to actually play the game. There are tons of graphics issues and crashes. It really looks like they botched the launch (on Steam, anyway.)
I would have been surprised if Rage was able to match worlds from companies like Bethesda, Bioware (before the EA buyout), or Obsidian.