Did you go to the wiki and read all of the notes from Fallout: New Vegas, or all the books in Oblivion? I sure didn't.
Going to the wiki to read stuff I missed from a FO/TES game? Ehhh... I would never do that... yeah... never *steps away nervously*
If what there is to discover, read, view, listen to, whatever is interesting and makes you crave for more, I'm all for it. Hell, even the Arkham Asylum record thingies got me hooked to the game trying to find them. And I could give a damn about the flags of Assansin's Creed for example, I'm not a "completionist". But things that have a history behind them? Something to uncover? Something to think about? I really like those kind of "collectibles". Just don't tell me that I'm missing 13 of the lost diaries of the dark knight thomas in a "Collectibles" screen when I didn't even knew he existed, that kinda kills the mood of it.