Thanks for your work on the wiki.
I'm not clear what you are proposing to do with the outline above? Are you proposing to re-organize the whole wiki? Or just add wiki categories or ...?
If you are planning a major re-write or re-organization, please post in the forum first and work with other frequent editors.
With that in mind, here are a few comments:
In general, I would say content on the wiki is a bigger problem than organization. Organization is definitely a problem, but no amount of organizing will help when the content is confusing and out of date. Bring the documentation up to date takes a lot of work, because it usually requires careful testing and/or diving into the source to understand what the current behavior actually is.
I would avoid putting pricing on the wiki, it's to variable and region specific to have be of much use to users.
I suggest not referring to CHDK as "firmware". Depending on the context, "software" or "build" is better.
