Ben Brooks wrote an interesting counterpoint to the rising argument that the medium of purchase is irrelevant, specifically that of eBooks vs. dead tree books:
I can tell you from first hand experience that the reading experience is very different on each of the different mediums and that’s why the distinction matters to me. I don’t care which version you bought because it changes what you read, but I do care because it may not be the same as the book I read (sometimes in the minor content differences, but always in experience and layout).
Curiously, Brooks implies that he cares what version others buy, which I overreaching. But the main point he is trying to communicate is that books are not books in all forms; some forms are superior to others. Brooks also thinks it’s extremely important to note which version of the book one purchased:
Perhaps the content isn’t different, but saying “there’s a great quote on page 51″ will yield very different results depending on the version you buy.
That’s why the differentiation is important. An iBook versus paper or Kindle book is a very different thing than the others. They will visually look different and that’s why it isn’t fair to lump the different types of book all into one category.
While that’s true, one has never said (or should never say) the page a quote is on in these general terms. If one is citing it, it becomes important to note exactly which version of the book it is. But if you’re referring to it in general conversation, there’s simply no need.
Marco Arment rebuts thusly:
Whether I’ve bought a book made of dead trees or encrypted bits doesn’t really matter, and I don’t think my experience suffers when I choose the bits.
Since I don’t think the distinction matters, I rarely need to say “I bought the Steve Jobs book in iBooks,” or “I bought the Steve Jobs book on my Kindle.”
I just say, “I bought the Steve Jobs book.”
The format is irrelevant in informal contexts. It’s what you’re reading, not what tool you’re using to do so.