While reading on the source code, I noticed that the function "get_default_cat_ID()" in file "inc/collections/model/_blog.class.php" returns the category with the lowest cat_ID (which is likely the oldest category). This is seen for example when creating a new post, the default category that is selected is this one.
I think it would be very nice if this default category was customizable for each blog, so that through the blog parameters one may specify the default category for new posts.
I guess this is not so much work (small hack in this function, maybe a small change in the database, and in the administration interface) and it would be useful for many people that always forgot to change their message category, like me...
Or maybe it would be a configuration parameter in the user profile, so that different users have different "default" post category?