I have a good load of OReilly and other publishers books in dead tree format and I find them immensely more practical compared to digital ones. DRM (which would be a stopper for me anyway) is not the only problem but finding a good reader which doesn't require ages to draw a page if contains diagrams, is readable even with multi column pages with graphics (therefore 10" minimum) and doesn't cost a fortune.

Last time I attempted to read The Art Of Electronics on a eink reader it required like 10 seconds for each page, so I gave the reader to a relative of mine who reads text only novels and stuck with the paper version of TAoE. Wake me up when technology is there.