As far as I can see, only one XML-RPC editor has nailed category selection. Blogware allows Publishers to created nested categories with no theoretical limits as to how deeply they can be nested. I have some internal blogs that nest eight or nine categories deep.

Desktop weblog editors don't typically handle this all that well. Take Blogjet for example (pictured right) - it has a drop down menu that allows me to select the category that I want to post the article to. Two problems with this particular implementation - it doesn't allow me to select multiple categories and it truncates the display of the entire category label. This leaves me unable to tell the difference between Internal/Documentation/ThingsINeedToDocument and Internal/Documentation/HowToTakeOverTheWorld - Blogjet isn't alone in this regard, w.bloggar has a similarly crippling interface.

Newzcrawler does it get it right though. Check out their implementation pictured at the right. Rather than forcing everything into a presized drop down menu, the NZ team saw fit to implement category selection in a scrolling, resizable frame that allows me to select multiple categories and view the entire category label - no matter how nested the category is.

Nowadays I find myself using BlogJet for most of my original posts and Newzcrawler's BlogThis module when I want to quote something that another blogger has created. My dream editor will accomodate both of these behaviors in one standalone tool. I'm not crazy about having my aggregator and my editor too tightly integrated - I'd rather pick the best of both worlds.

[For bonus points, click on the Newzcrawler screen capture at the left for a full view of the entire Newzcrawler editor in action.]