Microsoft collects information about you, your devices, applications and networks, and your use of those devices, applications and networks. Examples of data we collect include your name, email address, preferences and interests; browsing, search and file history; phone call and SMS data; device configuration and sensor data; and application usage.

This isn’t the only thing Microsoft is collecting from Insider Program participants. According to the Privacy Policy, the company is collecting things like text inputted into the operating system, the details of any/all files on your system, voice input and program information.

via Using the Windows 10 Technical Preview? Microsoft might be watching your every move to help with feedback.