The biggest change will be for anyone that has a Google Account. Under the new policy, if you’re signed in, Google will combine information you’ve provided through one service with information from another – meaning that you will be viewed as a single user across all of Google’s products.
Search Plus Your World is a great example of how Google plans to use the data it collects about you. Search Plus takes Google+ data and integrates it into search results on its website. You can now see photos that your Google+ Circles have shared, as well as posts and people that are relevant to your search.
The motivation behind the update isn’t just to include videos, but rather it’s part of the company’s larger goal of creating a “single unified, beautiful product across everything,” as described by Larry Page. Google was careful to note that it’s committed to data liberation and you can still opt-out by exporting your data through Takeout.