It will be interesting to see how things pan out, but I'm willing to bet that bookless libraries will be a fad this time around and they won't be a lasting fixture in society in my lifetime (and I'm still pretty young).

There are just too many wrinkles to sort out. There are too many books that exist just in print, and will probably never see the light of day electronically. Devices are an issue for the poor and those without the skills to use them. (Even if libraries lend out ereaders, running out of ereaders means that patrons don't have access to any ebooks. Running out of copies of a particular book leaves the option of reading another book.) On the library's end, there is the issue of copyright and restrictions by publishers. Then there are the people who just prefer books.

It would be wonderful if the world could switch to ebooks, but let's be realistic here. We talked about paperless offices decades ago, yet we have yet to go beyond a blend of electronic and paper. There are many reasons for that, but most of them come down to this: technology is rarely as powerful as people suggest and society is an extraordinarily heavy weight to move. Why should we expect ebooks to be any different.