I needed to be be able to sort the entries in a wp-ecommerce site that I am working on and the only plugins I could find were for the pre-3.8 versions.
This plugin tacks a sort order field onto the end of the category edit page. The update to the SQL is a bit rough so I’d be interested if there is a cleaner/safer way to detect which query to change the sort order for but for this version it does the trick nicely.
The sort order of blog posts is unaffected. Each category can have it’s own sort order.
If you have different sort requirements it should be quite straightforward to extend the dropdown options and add to the sql result.