Rob Latham's short piece "Against Textual Idealism," published a few years ago but first read by me a couple days ago, hits all the right notes for me as a librarian, scholar, and collector of SF:
It matters intimately to an informed grasp of Dickens’ novels, for example, that most of them were released in serial form, an arrangement that had appreciable effects on such intra-textual features as plot and characterization. Every text, whether an original publication or a reprint, is materially instantiated in a specific medium, accessible through particular modes of distribution, and amenable to discrete forms of reception. Encountering a story by H.P. Lovecraft or Dashiell Hammett in a pulp magazine such as Weird Tales or Black Mask is not the same thing as reading it in a Library of America edition.
I can't say it better, so you might as well just read the whole thing. (To tie it into issues of recent relevance, I think these issues of textual interpretation are more than relevant to Richard Dawkins' unrefined and totalizing view of the Bible. On a more gut and personal level, though, it just means it's way more fun to read an issue of Galaxy than a clothbound scholarly edition.)