I marked 1... because I like to read 1 book at a time. That is even easier with my reader since it is so portable.
I am also started listening to an audible while I got out of my daily walks. Not sure if you count this as "reading" or not.
So, now a days I will have 1 print/ebook in progress and 1 audio book in progress. I also read my AOPA magazine. I am actually quite behind on that because I have been reading so much more with my reader.