I don't really understand what "carnivals" are, or how they work. What I do know, however, is that my blogger friends are all doing it (Maria, Jay, Jen) and Maria went so far as to request that we post about it. So, this is a post about it. This month's carnival will be hosted by Jay Sennett. I don't really know what it is, but I'll check it out -- you do too. I actually submitted an article to it (though I don't think it's worthy of extended circulation), my recent post entitled "How do you know?".
[UPDATE] Maria sent me an e-mail explaining all this stuff; I've copied it below.
Carnivals are like intros you see at the beginning of anthologies, where the editor often says a little about each of the stories you are about to read - except carnivals are done with blog posts instead.
It’s kinda like if you were to publish a post of links to other blog posts you found interesting, but carnival hosts rely on submissions to link to.
I hope that makes some sense. There's also a FAQ page at BlogCarnival.com, which explains blog carnivals like this:
"A Blog Carnival is a particular kind of blog community. There are many kinds of blogs, and they contain articles on many kinds of topics. Blog Carnivals typically collect together links pointing to blog articles on a particular topic. A Blog Carnival is like a magazine. It has a title, a topic, editors, contributors, and an audience. Editions of the carnival typically come out on a regular basis (e.g. every monday, or on the first of the month). Each edition is a special blog article that consists of links to all the contributions that have been submitted, often with the editors opinions or remarks.
There is so much stuff in the blog-o-sphere, just finding interesting stuff is hard. If there is a carnival for a topic you are interested in, following that carnival is a great way to learn what bloggers are saying about that topic. If you are blogging on that topic, the carnival is the place to share your work with like-minded bloggers.
Blog Carnival is the place to come to find carnivals you are interested in, to submit your blog articles to carnivals where they belong, and to organize and maintain carnivals."