Yes, I do believe weblogs have forced those who practice “Journalism” (the profession) to work a little harder, and to not be as sloppy as often.
As an aside - the word “Journalism” is dervied from journal for which one of the offered definitions is “a daily written record of (usually personal) experiences and observations”. Hmm - this sounds like a weblog. So if a weblog is a form of journal, then presumably we can say that those who keep weblogs are practicing journalism - by definition?
Of course in common usage “Journalism” (especially when capitallized) is often used to describe the profession associated with newspapers, magazines, and (sometimes) television.
So … those who keep weblogs are “journalists”, but not “Journalists”?? Is this something of a rather fine - or perhaps slight - distinction? This change from centrallized to decentrallized mass communication (from print to the Internet) is playing havoc with old definitions :).