EBooks

I noticed that the new USCF sales page will includes some ebooks.  Anybody know what format they are using?  Do others have existing chess ebooks sites they like? 

I have never read a chess ebook but I find myself taking my old school hard books and playing through the positions using Rybka/Houdini, etc.  I find it very helpful to see a "diagram" for more of the positions than most books can show, it is also helpful for me to see if the computer analysis can supplment/reinforce/contradict/etc. the material in the book. 

I'm sure that chess ebooks are the way of the future, the first step for me is finding the sites/programs/guis/etc. that work best for me so I welcome the comments/suggestions of others who have already started reading chess ebooks. 

I have a bunch of interactive chess books and they are great!... Check out, eplus books ,and check out Everyman chess book viewer at Everyman chess.com....... In my opinion eplus has the best format but Everyman has the best selection