What Do You Look for When You Buy a Book?

I've been doing some research on my next ADO.NET v2 book project so I've been reading several different ADO.NET v1 books trying to get a feel for what they did well, not so well, etc. I've read up a lot of reviews on these books which has helped me ge t feel for which ones did well. But I thought I would open the floor and ask ya'll what you look for in a book. What makes you take it off the shelf and, more importantly, read it end to end. Feel free to give your constructive opinions on what some of the existing ADO.NET v1 books out there did well and not so well, I know Sahil and I are both writing about ADO.NET and would love to hear some comments from ya'll. Thanks ahead of time!