Given an array of post data to insert or update, it is easy to add a Post Format to the taxonomy array (similar to the `category` or `post_tag` data). The following assignments can be using in a conditional statement to automatically attach a Post Format to a saving post.
I’m currently using Theme Hybrid as a parent theme and have been exploring the internals with an eye to using WordPress 3.1’s new Post Formats for a lot of my content. I import my tweets from [Twitter](http://twitter.com/) via [Ozh’ Tweet Archiver](http://wordpress.org/extend/plugins/ozh-tweet-archiver/); I import my bookmarks from [Delicious](http://www.delicious.com/) via [FeedWordPress](http://wordpress.org/extend/plugins/feedwordpress/). These imported posts were previously stored in Custom Post Types, but Post Formats seem like a better fit, especially with the [hoops I jumped through](http://bajada.net/2010/10/12/custom-post-types-in-the-loop-using-pre_get_posts-refined) to get them to appear in The Loop.
The following explores options in Theme Hybrid for using a child theme to create custom Post Formats.