An editor on the German Wikipedia has proposed an alternative approach to the personal image filter -- I provided a translation here
http://de.wikipedia.org/wiki/Wikipedia_Diskussion:Kurier#.C3.9Cbersetzung
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1. There is no central categorisation of all images in different filter categories.
2. Instead, a new "hidden" attribute is introduced in Mediawiki when adding an image. "hidden" has the following effects:
- Unregistered users see the image "hidden", meaning it is not visible.
- One click on a show/hide button displays the image, another click renders it invisible again.
3. For registered users, there is a new option for "hidden images" in the user preferences: a) invisible, b) visible.
4. There are no separate categories.
5. One and the same image can be "hidden" in one article, and "not hidden" in another (principle of least surprise).
6. The same image can be "hidden" in an article in one language version (e.g. Arabic Wikipedia) and "not hidden" in an article in another language version (e.g. French Wikipedia). Each language version has its own community and can determine the use of the attribute according to its own guidelines and policies. Cultural aspects can thus be given due consideration. This is exactly analogous to the current principles informing article illustration.
7. This solution would leave it to the individual wikis to decide which images are encyclopaedically relevant (informative, illustrative) – but still "critical/controversial" – in which articles. Images of spiders could be handled in the same way as images of Muhammad, sex or violence.
8. The presentation of images outside of the article context – e.g. in galleries for Commons categories or Commons search results – would require a separate solution, perhaps to be implemented in a subsequent phase.
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What I like about this proposal is its simplicity and elegance. It has the great benefit of leaving the communities and content writers in charge of where and to what extent they use the filter, and it also includes non-logged-in users.
Andreas