With this policy, Google has the ability to deliver more relevant search engine results pages to a user’s query. This will be the case for Paid Ads as well.
But how is this going to work? You may ask. — Allow me to illustrate with following example:
A user has expressed interest on jeeps on his Google+, he watches jeep videos on YouTube, and received emails on his Gmail account about new jeep soft tops. When this user searches on Google.com for the query “bikini top” Google may display ads for bikini tops for jeep instead of the clothing related query.
The same will happen with SEO, staying with the “bikini top” scenario, Google may rank jeep stores that sell bikini soft tops versus any clothing store selling bikinis.