Great post, and a great idea Iraê to add Delicious into the algorithm. I agree that we should be using other search engines and also like comparison engines such as http://blindsearch.fejus.com/ but believe it will take a huge upheaval for what we have learned as a species over the last 10 years to change behaviour on the sort of scale needed to alter the statistics as above. Google has fallen foul of it's own algorithmic success and is at a stage where diversification seems to be their strategy rather than adding in other methods for improving results. Personally I can't see Google winning and am keen to see what new players will come into this space. I believe more complex algorithms that search multiple resources and think/calculate longer before results are returned could be the way to go.