iBooks feature request - sort by last opened

So one thing drives me crazy about iBooks. I load novels that I'm reading, and reference manuals in there (like for my car or stereo receiver). So when I need to pull up a reference manual and look something up, that goes fine. But later I pull up iBooks to read my novel, and I'm still at the reference manual. Now I have to search or scroll (I have over 600 SF novels in iBooks) and try to recall where the book I read was.

How about the ability to sort by the date the book was last opened?