The policy is generally innocent, but there's a specific paragraph that could be used for good, or not so good purposes:
Under the new policy, data you have anywhere stored on your Google Account will still appear under Dashboard, but any of the services in the Google world can interact with this data without notifying you.
For example, when you look up a location on Google Maps and are signed into your Google Account, when you later go to YouTube you could be shown relevant videos to the location you searched on the homepage. Google gives the example that they could give you a meeting reminder on Google Calendar due to your Google Latitude location, or the company can offer spelling suggestions in search based on your contacts usernames.
All of these are useful things, and will enhance Google's services over time. Google isn't unifying some products, though, with Wallet, Books, Chrome and Chrome OS having their own seperate policies still. Simply put, the new policy makes understanding the privacy rules very simple. They've even been cut right down and can be read through in less than 15 minutes now.
The not so great
Despite this, we need to look at what Google's really doing here but not saying. We've seen the company pushing integration across services lately, such as the desperate push of Google+ search results in the companys redesigned search pages. What does it mean we'll see the company attempting to share in the future?
Google already has the rights to read your email for advertising in Gmail, but the new privacy rules mean that it can extend this information past the walled garden of your inbox. Technically, if you were talking about getting married with your friends in an email, Google could show you videos on YouTube that are related to weddings next time you visit, and sponsored stories on Google.com could be wedding related too. This could get you in trouble, especially if your fiance-to-be didn't know yet.
That's an extreme example, but with Google's wide variety of services, they can now share data between sites about where you were today, what you purchased, who you talked to, what you watched, what you searched and who you were with. It definitely seems like the company wants to know everything.
These changes give new levels of information access to system administrators, too. They will now have access to any service you access and that data belongs to them. Where you travel with your work Android device could now have job implications. What you view at home, while accidentally being logged into your Enterprise Google Apps account could mean you have an awkward conversation with your boss.
Unification is great, if you can disable it or are aware of it. The power should be in the users hands to link the data accounts together, or they should be aware of the implications of their actions. Organizations need to be able to break the link between search history and YouTube's reccomendations if they choose.
It's too early to say now if this is Google's plan, or even if the company is considering this, but the policy is so loosely worded it could be an option.
The reality of free
Users love free services, and many of us are willing to just hand over information without batting an eyelid if it means that it's free. The more technical minded among us may shout "Google is evil" and "abandon ship" but the average user really doesn't understand the implications of such a change (nor do they care), and will click the "I agree" option to just get to their inbox, or watch that YouTube video.