Now, the fact is that people do try to post such “trolling for readers” comments, vacuous or irrelevant comments that serve only to advertise their link on my web page, and I remove those in the moderation process — I simply reject the comments, and y’all never see them. A pox on those people.
But Maggie can hardly be accused of doing anything of the sort. Her comments are always to the point of the post she's commenting on, and she always has something to say besides just, “Nice blog, come look at mine,” which are the sorts of things I filter. The same's true of the other comments that get posted, and I'm grateful to the commenters, both regular and occasional. A link to your blog is the least thanks I can give you for sharing your views.
But more than being tokens of thanks, the links are, in fact, what add value to the web in general and to blogs in particular. The concept is that information is all interlinked. You find something you're interested in, and there's something related that's linked off of it. It's a web of information.
Any attempt to overlay a structured taxonomy or ontology on an information source as chaotic as the worldwide web is doomed to failure. Technorati and del.icio.us tags, and those sorts of things, allow the users of the information to develop an ad-hoc ontology in the same chaotic way. And blog links are part of that.
In fact, I got to James's blog (Dr Momentum, Maggie's husband) through Maggie, but hadn't actually gotten the link to her own blog until she put it in yesterday's comment. And there are a number of blogs that I read which I found through comments their authors left here or on other blogs. If I find a blog interesting, I might find things interesting in other blogs on that person's blogroll, or in the blogs of people who comment there. Those links aren't just a courtesy to the target of the link; they're also a service to the readers.
So yes, if you have something to add to the discussion, you get a link. And from there, maybe people will find other interesting things you have to say, other interesting things your blog may point them to, and we'll all travel the blog world from our sofas, laptops to hand, cats by our sides.