I do both read books and listen to audiobooks. Sometimes audiobooks give me a jump start into a book I want to read. Once I get past the beginning of the book on audio, I will pick up the actual book to finish it more quickly. Lately though, I will either listen to the book, or read the book--depending on what my preference is for that specific title.
I don't have any criteria for deciding what I will do on audio versus what I will read. Sometimes it is just simply convenience. If I have the audiobook, I'll listen to it. If not, I will read the book. Other times I will listen because I know there is no way I could actually finish the book if I were reading it (I have a little attention problem with books--if it doesn't hold my interest I find myself easily distracted). Audio books help me avoid that problem--as long as I have them playing in my car I will keep listening allowing me to finish the book.
Last year I went through a big dry spell with reading. I could say I suffered a book burnout. I simply didn't want to sit down and read anymore. I lacked the time, I was stressed, and after several deaths in our family I lacked motivation. I can't say that I know for sure what caused it, all I know is without audiobooks, I probably wouldn't have read anything last year. Audiobooks reminded me why I love to read and got me reading again.
Audiobook Week is hosted by Jen at Devourer of Books. Visit her website to find out more or to participate in Audiobook Week 2013.