The internet has made my life as a graduate student so much easier. Research takes about a tenth as long as it did when we had to sit in the library and dig books off of shelves. Now I can just look up articles and download the pdf!
However I think the internet has also made people nastier in general. It makes me sick to see some of the comments people put on the internet while they hide behind their electronic veil. It is easier to stalk people (facebook, anyone?) and to ruin someone's life (identity theft, hacking).
Society wouldn't be the same without the internet, but I think we would be fine. Sometimes I wonder what would happen if infrastructure crumbled and we had to go back to small societies and self-sufficiency.