Judging by posts and comments by graduate students in math.stackexchange.com and mathoverflow.net, I have come to the conclusion that a large part of their knowledge comes from SE sites and the Wikipedia, as opposed to traditional publications such as books and papers.

I was deeply shocked the first time I heard of a student researching the literature through Google, which spits out at least as many SE and Wikipedia answers as references to books and journals. But, of course, nowadays I do the same, certainly more often than going to the library!

Are traditional publication forms becoming obsolete, in the face of purely electronic forms? Or, contrariwise, do younger people who ignore traditional forms miss out on essential information?