I’ve implemented Asides here on my blog. Mostly to allow for content that doesn’t deserve a full post – Twitter for my blog so to speak.
The Aside posts are also styled differently and it’s pretty easy to accomplish using the in_category() function in WordPress.
I’m also able to use the QuickPress feature of the dashboard as well as the Press This bookmarklet. For now, I have to set my default posting category to Asides as QuickPress doesn’t allow you to select a category. (Coming in WP 2.8)