The obvious benefit to society of the web is the availability to almost every human being of instant world-wide communication. Even remote tribes in third world countries have access to the web via satellites.
Resulting benefits: Tyrannies exposed. World wide standards of human rights are achieved. Example: recent Middle East revolts toward democracy. There is a worldwide exposure of cultures to one another, resulting in increased tolerance, compassion and understanding.
Down side: More reliable and academic information sources are ignored. Newspapers will be phased out. The U.S. Postal Service is in decline. Interpersonal relationships are hindered in terms of reduced conversational ability, impaired social interaction due to distraction with hand-helds, lost ability to spell, compose and write, increased motor vehicle accidents due to distraction. There is a deleterious effect on the creative arts.