Facebook, Google and Yahoo want to know as do all their advertisers.

Google dominated the web by facilitating searches based on words, phrases and the pages containing them. Links from one site to another along with the volume of traffic counted in determining the most relevant pages for a searched term thus creating a successful search engine valuing the interest in specific words as an advertiser media. But words alone and links to the pages they resided on are no longer the most prolific source of relevant referrals — instead, people sharing content with other people via social networks like Facebook and Twitter have become the new grail of relevance and bankable targeted messages.

Google is paying social network sites for access to their public updates, but it does not have access to the personal profiles or the intimate details that Facebook does of those engaged in the sharing.

Facebook is building a potentially more powerful search engine: One that delivers search based on relationships and interests to value relevance. With the innovation of the “Like” button, Facebook will know more about individual preferences than those that preceded them.

Competitively, Google may be in a position to “buy” a solution or give one away. In fact, Google confirms free turn-by-turn directions coming to iPhone.

Free turn-by-turn Google Maps Navigation has already threatened an entire industry of GPS navigation companies whose livelihood depends on selling paid versions of what the search giant is now giving away for free. Currently Google Maps Navigation is available for Android phones only, but Google said it will bring free navigation to the iPhone along with other platforms.

Real time and historic proximity data coupled with actual purchases is proving to be valuable media criterion for advertisers seeking direct retail purchase performance metrics. Traditional branding campaigns are aggressively transforming into a direct sales influence on the internet and mobile platforms.