Split this off to keep the Q&A thread streamlined.
Not to put down the various blogs, I'm a big fan of several of them, but I don't believe that the concept of a "major Nats blog" exists. Zuckerman's was the only one and since he is now an official member of the media again he no longer qualifies.
I wouldn't know. Traffic has been good when you look at it from a year-over-year perspective, especially considering some of the rotten teams that have been put on the field, but statistics are just numbers... I try not to read too much into it. My main concern is making sure the forum can handle anticipated load, hence the big upgrade late last year in anticipation of a bigger year this year (hopefully a lot bigger, fingers crossed)
Post count has risen steadily by about ~30% per year, with the exception of a 9% drop from 2009 to 2010. Page views for the last three years have been pretty steady at just under 10 million, with a dip to about 9.5 million in 2011. New topics has dropped steadily each year, presumably because of a general tendency towards more monolithic threads. Averaging about 400 new members per year for the last three years, prior to which I didn't have any anti-spammer measures in place, so the numbers for '07 and '08 are totally meaningless. Obviously only a fraction of new members become regular posters. Hard to say how many lurk.
Any forum member should be able to see the stats page, but I suspect most people aren't aware it exists - http://www.wnff.net/index.php?action=stats
I don't have readily accessible stats for 2005 or 2006 due to the use of a different forum software in those years that didn't keep track of such things.