Social networking sites like twitter and facebook provide better real time search results with latest happenings. Google is trying hard to make search results as relevant and specific as possible, infact it has even partnered with twitter to display tweet as real time content.
Social networking sites definitely have the possibility of giving competition to google. In addition to this social media and bookmarking sites such as flickr, Digg and delicious will also be very popular for search in coming future.
Social media and networking sites will be a hit in search results because they can provide better location based results as they have information via profiles bios also social sites will not use algorithms to display results and rather they will have this human touch which only improves search and takes it to a new level.
Do you still think Google will dominate?