ENGINE TAKES PRIVACY EXTREMELY SERIOUSLY.
We want to earn the trust of all our users so that they know Engine is a safe and secure service to use.
First, to address the use of "APIs" which allow Engine to connect with your existing apps and online services. It is important to be clear that Engine will NOT be storing your username or password to these other services. The way that Engine will connect with your data stream is through a program called OAuth2 which is used by Google and many other large internet companies (you can read the technical details about OAuth2 here http://code.google.com/p/google-api-java-client/wiki/OAuth2 ). This system allows Engine to have certain permissions to pull the data from your existing apps without giving Engine access to all your usernames and passwords.
Second, when we say that Engine is going to "link together your apps" we do NOT mean that it is going to expose your information on one service to all the users on another service. So for instance connecting your existing services will NOT automatically begin streaming your YouTube views to your Facebook or Twitter feeds.
What Engine will do is give ONLY YOU a place to view all your information in an organized user interface that displays the information that is most relevant to what you are working on.
Our model is the opposite of those who want to monetize your information by sharing it far and wide. The Engine team has a vision for putting the USER back in charge of their own raw data, instead of a 2nd or 3rd party.