That quotation is from Patrick Nielsen Hayden, the Tor publishing editor responsible for editing some of my very favorite books, and a long term blogger at Making Light. The quotation is from this essay here at Tor.com about blogging. The entire piece is very much worth reading, but PNH's central point is in that pull-quote. It's one of the smartest things I've ever seen anyone say about blogging, in that it captures the idea that blogging is about conversation. As a blogger, writing posts read by people you don't always know, you're the host at that party, and you want your readers to respond by leaving comments. That's the conversation part; you as a host, introduce a topic, but you leave room for your guests to comment, and reflect, and let you know what they think. That's part of what creates a good party, and it's how to build community online.

On the joint Nielsen Hayden blog, Making Light, there's a note in the sidebar:

Our readers are the best thing about this weblog. If you’re not reading the comments, you’re missing half the fun.

At a really good party, half or more of the fun is in interacting with the other guests; guests that the host has carefully selected, and taken pains to introduce to each other. Much as you would start conversations between guests at your party, you want to foster conversations between your readers via the Comments.

I don't know if Patrick Nielsen Hayden was directly alluding to much earlier discussion by Doc Searles about how the Internet is changing markets, but Nielsen Hayden's remarks and an earlier essay by Searles both reflect the idea that readers, and customers, are different on the Internet than in the real world. Doc Searles in The Cluetrain Manifesto writes about the ways the Internet has changed markets and how customers and businesses relate to each other. Searles notes:

A powerful global conversation has begun. Through the Internet, people are discovering and inventing new ways to share relevant knowledge with blinding speed. As a direct result, markets are getting smarter—and getting smarter faster than most companies.

These markets are conversations.

For the purposes of blog posting, and comments substitute the word "readers" for the word "markets." On the 'net, readers are not isolated from each other in quite the same ways they are in the analog world. Comment threads are one of the ways readers interact with each other, and with posters. The idea is to encourage your readers to interact, and comment, not just with you and your post, but with each other. Part of your job as a blogger is to host the conversation.

A friend who runs a very large online community for writers compares the community to Rick's Cafe in the movie Casablanca; "Everybody comes to Rick's."

With "everybody" potentially being able to come to your blog, and comment, you need to make sure that "everybody" can participate in a courteous but honest fashion. That means not only inviting and encouraging reader comments and participatation—and link-backs, it also means setting a tone that is appropriate for the blog, and the particular kind of community you want to foster.

Your readers are the entire point of blogging, unless you want to be like the person who stands in the middle of someone else's living room and declaims at a cocktail party. As another very wise writer puts it:

Give good value. Be useful, be entertaining, be engaged. If you're interested in things other than yourself, you'll seem more interesting. The flip side is that if you're only doing a weblog to publicize your work, your audience will be able to tell, and they'll go away. Readers have a magic ability to suss out your motives.