The Advantages of Blogging are Deep and Wide

Ezra Klein's homage to effective blogging is spot-on:

So figure out where you add value. Find something specific to follow and follow it deeply. That "something" could be health policy, as it has been for me, or urban policy, or telecom, or congressional procedure, or media structure, or a thousand things I can't name. That's not to say you have to create a niche blog. The specialized posts mix with the generalized posts -- in my case, health wonkery rubs elbows with garden variety political punditry -- and the two cross-subsidize each other. The rigor of the more technical work gives you credibility in the reader's mind and adds weight to the generalist posts. The generalist posts broaden the blog's potential audience and create access points that new readers wouldn't have if you let the blog become a repository of technical commentary.

The great comparative advantage of blogs is that we're freed from the essential scarcity of print: Space. Deep content need not fight for pages with broad content, and so you can have the advantages of both. You can go deep without alienating readers and go broad without sacrificing depth.