What discriminates science journalists and science bloggers?

A recent opinion article in Nature may serve as my diving board here. Althoug texts are much better edited by professional journalists, the content isn’t better (driven mainly by press release). And of course, journalists must write about topics outside of their knowledge zone. Funny, they resemble

more that of a priest, taking information from a source of authority and communicating it to the congregation.

Journalists don’t have enough time for the details while bloggers can restrict themselves to their main expertise ;-) raising also a large amount of public awareness.