In the case of software, I was kind of keeping the number "5" in the back of my mind. 5 articles (out of a set of 30-ish) probably warrants a subcat. So, if someone made a page for [[Safari]], [[Firefox]], [[Mail.app]], [[Tomato Torrent]] and [[Cyberduck]], I'd make an argument (or an action) to create a "Internet and Networking Software" subcategory under the "Software" category. Likewise, down the road if there's articles for Safari, Firefox, Camino, Omni and Internet Explorer, I'd make the argument for a "Browser Software" subcat of "Internet and Networking Software" category. Them, I suppose, in the distant future, when dogs and cats get along, and someone creates articles for a bunch of Firefox plugins, i'd want to subcat "Firefox Plugins" under "Browser Software".
In the beginning, I was trying to lay out the eventual categorization, but the community convinced me that we should categorize after content.
So. In summary. (My) Rule of Thumb is: No new subcategories without at least 5 articles, and definitely no new categories without group consent.
(PS: look at me trying to wikilink all those things. I'm going to leave them wikilinked, in case Arn wants to hack up vBulliten.

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