I didn't answer the poll as my answer is lately, I listen to audiobooks almost exclusively. I listen on my phone so it's always something I'll have with me. Whereas no matter how lightweight the e-reader is--it's another item in the bag or purse.
I listen to books on my train commute and while doing chores. I don't drive but did listen to books when I rented a car over the holiday. Basically listening to books has replaced listening to music and podcasts. It has also replaced dead tv viewing time. This is the time when I'd have the tv on just to have it on or watching rerun. Now I turn off the tv unless it's something I really want to watch. I'm plowing through more books now--for me. Compared to many here, I'm not a big reader. But what used to be 15-45 minutes a day of reading now stretches to 1-2 hours of listening.
It is easy to drift away from a story so I do have to remind myself to pay attention. It works for when your mind isn't particularly occupied. So listening to books is perfect for washing the dishes and doing the laundry for example. I work from home a lot and I never try to listen to a book while plugging away at a spreadsheet--as much as I'd love to. It would be a waste of the book.
I've also stuck with lighter easier reading material with audiobooks. Right now I'm finishing up the Millenium Trilogy which is perfect audiobook fare. I've got Bring up the Bodies next and it may be the first "serious" audiobook I'll try. I read Wolf Hall in book form and as great as the book was ultimately--it was such a slog. The font was too small, the lines too close to each other and I didn't want to carry the book around. It took me an embarrassingly long time to finish the book. I knew I wanted to read the followup but no way was it going to be in book form. So I ripped the CD of Bring up the Bodies. If I find the book is fare that better suited to reading, I'll borrow the ebook.