For Google, it's personal. The Internet search giant is no longer going to roll out the same search results to everyone.
Senh: I've already been seeing some of that in action. I've noticed that the results I get when I'm logged-in are different from the results I get when I'm not. Sometimes, I get results from sites that I'm Plus One-ed on. Sometimes I get results from sites that I visit often, like MoviesWithButter.com, for instance.
