As someone in the 100+ club I agree with most suggestions allready up.
Last year I set a goal to read 100 books, pushing myself. I got 108. Year before was 81, 49 before that and in the years before i averaged 10-15 since I was 18 (now 26). (I can give you the numbers because I use Goodreads to track my reading). This year I'm aiming for 100 again, pushing beyond that will be too much for me though and I think next year I will cut back to around 60-80.
I read that much because I trully enjoy it - for a variety of reasons, pure enjoyment first of all, learning and self improvement, because I'm a writer and working on being a novelist and for me reading is homework. Even just for an escape and to broaden my mind. I read quite widely, fiction, non-fiction - its all good.
Getting a kindle in late 2010 was the real tipping point in my reading (2010 was the 81 book year - year before with 49 I really made a commitment to read more and had lot more spare time). The kindle just makes things SO much easier to read more. I also sync my kindle with kindle app on my phone so I can read absolutely anywhere. If I have just a spare minute I'll be reading. My dad only reads a book when he is taking a dump, but that bit of time every day means he reads probably more than the average person.
Beyond that, I tear through most non-fiction using the same method Tuthmosis mentions, looking for what is the filler. Even some fiction you can just recognise ok, this bit is shit, excess descriptions or fluff - speed read or just skip through it to dialog or action that is driving the story forward.
I can speed read to a degree, but I dont get the same level of comprehension and knowledge retention. My hat goes off to those who can speed read and still achieve good levels of both. The basics are just scanning each line rapidly, resisting the urge to pause - then just building your speed.
I always have at least 2 books that I'm reading at the same time. Usually one fiction, one non. I alternate depending mainly on mood and energy. If a book is boring me I will leave it for a while, come back and try again, if its still shitting me - bin it. Even before my kindle I had a second smaller bookshelf filled with on average 10 books that I wanted to read. So if I felt like reading some action I coulf, if I wanted to learn there was a few options, if I wanted some sweet inspiration there was always a bio there as well. That way there was no excuse not to start reading that next book as soon as I finished. Kindle makes this SO much easier, I often have like 40 samples downloaded to my kindle allowing me to make a start, read the first ten percent of whatever catches my attention and then buy it if I'm enjoying it then continue reading. It's like having your own huge public library to browse.
For me audio books are too damn slow, my usual reading speed is often double the readers speaking pace and it pisses me off knowing I'm flushing that extra time down the drain. However downloading them to my computer and speeding up the pace (easy done even in WMP) produces good results. Now I use the kindles read out loud a fair bit as well if im working out, cleaning, cooking, etc. I rarely listen when I'm driving though - personal choice, I like driving to my tunes and find I dont pay enough attention.