Google has finally allowed you to modify the search results – SearchWiki. Of course the modifications will be only for you, otherwise rest of the Google would not make sense. But you can now improve the search results by reordering/deleting/adding individual entries. It was an amazing experience when I had discovered Swicki quite a while back, I wonder why Google was so late. I have not been able to test-drive SearchWiki yet, but I wonder if it might also lead to confusions.
People will have to be aware whether they are logged into Google or not. Many of us do use one of the Google services, so we are logged in, but we are not aware when we use its search. It made no difference till now. So, if you do end up modifying the results, make you sure you are logged for your future sessions. Also, would this affect Google Custom Search as well?
You also have to be more careful when you send links for search queries around. One of your receivers might end up seeing his/her modified results instead of what you wanted to show.
Having said this I feel that this is a positive development. It will be interesting to see if this additional power to the user gets abused, and very interesting to see if it will clash Google itself.