Elizabeth Lane Lawley says this about blogs and ideas (thanks Hylton!):

Most of the blogs that I read regularly go well beyond link-and-comment. If they link to an “idea du jour,” they do so because they have something to add, a new direction to explore. As a result, it’s not so much an echo effect as it is an opportunity to watch an idea emerge, grow, diverge, expand, be refuted, etc. … The interlinking of ideas and content on weblogs, particularly given the linear time-based nature of the form, provides a fascinating window into the evolution of an idea.

Link-and-comment blogs are great because by and large they are updated so often (drive-by blogging!) that there’s generally a lot of *there* there, in terms of numbers of posts. Even if the poster hasn't necessarily added much to the original idea, by doing the drive-by thing they are at least pollinating the idea to someone who may have time to comment.

I agree with Liz, though; the blogs I tend to like best are also those that go beyond link-and-comment. And as a blogger I always feel like I've cheated my  readers if I do too much drive-by posting and not enough commenting.

One particularly blog-specific method of building on ideas that I like to read and often use myself is to link to the original citation, add a comment, then use other links to related ideas to start fleshing out the divergent path suggested by the comments. I do this because I’m at heart a researcher--though I wouldn’t call myself obsessive about it (some have, though!). Research is the way I make sense of the world and ferret out connections. I don’t necessarily have to see every single citation of a post before I’ll comment on it, but I do like to dig a little into the subject, and/or related subjects, and see if a new connection presents itself--what would you call this, search-blogging?! Except that I generally don’t link to the search results, but examine some of them and see if they suggest other maybe more productive search strings. The idea is to see if I can find any connections that might further the conversation around a particular idea.

I’d be curious to know how others feel about the various ways in which ideas travel through the blogosphere and “emerge, grow, diverge, expand, be refuted, etc.” Is there a favorite blog “style” you like to read or to write yourself?