Merlin Mann lists some attributes of good blogs.
Good blogs try. I've come to believe that creative life in the first-world comes down to those who try just a little bit harder. Then, there's the other 98%. They're still eating the free continental breakfast over at FriendFeed. A good blog is written by a blogger who thinks longer, works harder, and obsesses more. Ultimately, a good blogger tries. That's why "good" is getting rare.
Like Merlin, I'm discovering fewer and fewer good blogs these days. Part of it is that blogging as I would define it is passe. These days people are writing for online magazines like Gawker or Tumblring or Twittering or Facebooking or doing a million other things on the web. But people are also listening to a bunch of bad advice -- CALL NOW TO FIND OUT HOW TO MAKE MONEY WITH BLOGS AND WE'LL THROW IN THIS JUICER ABSOLUTELY FREE -- instead of Merlin's level-headedness.