One of the things that gets stressed about the Qur'an is that it was an oral revelation. It wasn't (at first) written down. Susanne did a post a while back where the author of the book she was reading theorised that this enabled Mohammed to make edits and adaptations to his speeches as the need and/or mood of the crowd required. So while we may (and I'm not sold on this fact in and of itself) have the original version of the written Qur'an, totally unchanged from when Mohammed's followers wrote it down, we absolutely don't have the *original* Qur'an, because we weren't there and can never have heard Mohammed saying it.
And it's not just the Qur'an. The message of the Bible, every letter and Gospel in the New Testament was meant to be heard, not read. If for no other reason than the fact that the majority of the people at that time, and for centuries after that, could not read. It just wasn't practical, or helpful. Think about it this way. It takes a couple of hours every day for, heck, I don't even know how long to teach someone not just to read, but to read well. There's a difference. Trust me. It doesn't seem like much, does it? But in those times, there was a very, very small gap between survival and death for most people. Harvesting, dealing with livestock, selling their goods, working, cooking, cleaning, on and on and on. A million things that we don't worry about any longer but that they had to. Unless they were well off and therefore had idle time and money to pay for books and someone to teach them or they had necessity then reading and writing weren't that important to them.
But does it really make that much difference? Hearing versus reading?
I think it does. In the first place, if we are to hear something the way it was intended, then we will be in community, which is where our faith is meant to be practiced. Not alone, reading our sacred text and deciding what it means all on our lonesome, but *with* other believers. In the second place,we process things that we hear differently, both emotionally and intellectually.
As an example, I've been listening to books in my car for a while now. And I just recently listened to a death scene from a book I've read multiple times. The death is sad, and poignant and heroic. I'm sorry the character died, in spite of the fact that he's only in this one book, not even a recurring character. But I never *cried* for this character's death until I listened to it being acted out.