No. When you begin the Photoshop CS6 beta installation process, you will be presented with a Welcome Screen. To install the Photoshop CS6 beta, simply select the option labeled "Try. I want to try Adobe Photoshop CS6 for a limited time." Do not select the option labeled "Install. I have a serial number."
You will however, need to log in using your Adobe ID to activate the software for use beyond 7 days.