Blogs. Destroying the economy or improving productivity?

A report last week by Advertising Age Editor at Large Bradley Johnson noted that about 35 million workers -- or one in four people in the U.S. labor force -- spend an average of 3.5 hours, or 9%, of each work day reading blogs.

This blogification of workplace time is no minor concern -- the total losses across the national work force are estimated to be the equivalent of 551,000 years of paid time that is being spent on blogs via the employer's own computer systems.

Another important point was that the time spent reading blogs on the job was in addition to the time already spent surfing the Web in personal pursuits. The debate appears to be one of reasonable limits.

At what point, or at what length of time, does the use of company assets for personal activities become unreasonable? And is the problem likely to become an even greater one as more and more TV content goes online, becoming easily accessible from one's office computer? Do employers need to find new ways to police their computer systems? Or does Blogging and personal surfing actually improve moral and make people more productive in the long run? Your thoughts?