I think reading is subjective. I found that I could unwaste a lot of time by reading. I get the bus to and from work, and I have an hour lunch break. That's two hours productive reading for me, and that's not counting reading at home in bed or upon the throne.
Some books take longer to read than others, too. It might be the size that demoralises you (I get through physically smaller books quicker), or something else. I managed about 120 pages of a book today just using my lunch and the bus home (I was reading another book on the way there, but I didn't particularly feel like reading it). The book which came before, which is the same size bar two pages, I read in two days (Admittedly I read more than I normally would last night).
It doesn't matter how quick you read, as long as you're comfortable at that speed and pace. With my new-found addiction to buying books, I need to read faster and faster, and that's what I'm doing. Since the start of June I've practically read and finished three books, got 120+ pages into another and read a 220 page graphic novel. I would never have dreamt of reading this fast, and I can only do so because I use a few hours of my time more effectively than I otherwise would.
"Fish are not the best authority on water" - Jane Yolen; Sister Light, Sister Dark