I swear we had a discussion around here about this before.
I think the confusion about reading speed is from folks that read the most straightforward way (like a kid learns how to read). Like they read the words and hear them in their head, word by word. I haven't read like that since before I can remember so the concept is a little foreign to me. I really have to concentrate to read plays, poems, or old English because I can't "aborb" them the same way. I have to read the words and listen to the words to make sense of it - my speed slows down about 80% for that kind of material.
I absorb the book by the paragraph or so. I don't read the words and hear the words in my head. I just absorb the story into my brain - not the words so much, but the meaning and the events. I read about 2 pg/min (hardcover). On my Nook that's more like 4-5 "pages"/min.
I know I'm reading the words because my reading is very sensitive to typos, mispellings and missing punctuation (I bookmark them on my Nook to correct later in Sigil or something...if I get the time). My comprehension (on how much I can repeat back to you) is fantastic on dialog and story details. I do good on history tests too

but I find I tend to miss some of the descriptive detail from time to time (or at least, it doesn't stick in my memory for very long).