So Custo has submission tagging now. It's awesome and helpful. But only when you're using them properly.
Tags should be: Adjectives for your submission. A few simple words that gets the vibe of your submission across. Is your sub a picture of a forest? Tag it as "nature". Does it have a modern looking house in it? Tag it as "modern, architecture".
Tags should NOT be: A list of authors/skins contained in the sub. They should NOT be a category that already exists (screenshot, wallpaper, winamp). They should NOT be the name of your submission. Is your submission a wallpaper? Why are you tagging it as "wallpaper"? Is your submission called "WickedWeed420"? Please don't tag it that. Does your screenshot contain a winamp skin? You really don't need to tag it with "winamp".
Browse Custo by tags and you'll see a LOT of them that are:
a) redundant b) irrelevant to the point of searching by tags c) just plain improper usage
Good post Aero, this is definitely something the community can improve on.
For those who don't know, you can get to a list of all the latest tags at http://customize.org/latest/tags (from the Latest tab). This is a great way of monitoring whats being tagged, and helping to keep tags accurate and useful.
When tagging, try thinking of it from the point of view of trying to find something. Would someone search for 'minimal'? Yes. Would someone search for 'mycooldesktop'? Unlikely.
As Aero mentioned, there is no need to repeat categories, suites, authors or titles -- these things are already done in a more powerful way (you can think of them as special types of tags if you'd like). I do admit this is made slightly harder but the lack of fields on "power browse", but we are working on that.