Communication is not limited. My e-mail files are filled with correspondence from a large number of bloggers, some quite well-known. Sometimes I don't get answers, but a point I bring up is addressed in the blog later. It isn't as direct as comments here, and it isn't open to third-party response like comments here are, so in that sense it's more limited, but it works.

Look at this great post over in Space. Something remarkable, a result of someone focused closely on a single issue and doing the work to bring it forward.

Now that work stands out in public for comments by other interested people. Maybe mistakes will be pointed out, and corrections made. But certainly everyone has benefited from it.

This is true of blogs and boards on other issues, like politics. Hundreds of brains each working their own pieces of the big picture, and doing the legwork that a person integrating all the results couldn't do by themselves. Intellectual division of labor has long been a factor in our economy. We finally have it big time for news and information.