You shoulf improve the search engine in few ways :
- First use the popularity :
- In the pagerank way more a link is used more it is popular;
- Need to care about duplicate content calculate a MD5
- Need to add an option "this link is the same as"
- Query should be able to use special vocabulary for (-,+) picture case
- User tag should be enable especially for the consitency of pictures query answer, it should be also based on frequency ( to ensure spam proof at least a bit)

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