Although Google is using social technologies to personalize results – new features to roll out  over the next few days – it is only using its homegrown ones. Signed-in searchers using secure search mode will be able to toggle between personalized results that search Google+ and Picassa content and Google profiles. My GigaOM colleague Janko Roettgers thinks search will be a killer app that could increase Google+ adoption, driven by celebrities and photos. Perhaps. But so far, there aren’t enough Google+ users for this initiative to have a huge impact on mainstream search. It’s a classic chicken-and-egg problem that Google will have to push forward. The personalized search options would be way more powerful if they incorporated Facebook, Twitter, Flickr, etc., something Google says it’s open to. But if Google can’t work a deal with Twitter, how will it do so with Facebook?