Freed from the constraint of paper costs, prophets, pundits, boosters and just plain windbags go on and on and on about every conceivable subject. Perhaps because of this barrage of information and pseudo-information, most Web readers seem to skim through Web pages, devoting a lot less attention per word than they would if they were reading a print publication.
Most folks seem to agree that people's attention spans shorten when they go online.
When writing for the Web, therefore, it's wise to write a little tighter and meatier than you would for print. Remember that your readers can click away at any second, and try to keep their attention by sticking closely to your topic. Avoid repetition and superfluous clauses. Of course you don't want to economize so much that your prose becomes stilted and humorless. Really talented writers find a good balance, and are able to cover a lot of hard information in a readable, entertaining way.