The Blackberry Playbook will not have Sprint service, it is a "wifi only" tablet. It will also be sold as an "accessory only" for $499.99 // Since it doesn't have Sprint service, there will no contract renewal and no upgrade or new-line discounts available for the device. There will be a tethering option from an existing blackberry phone for $29.99 per month. Meaning, if you own a blackberry handset on the Sprint network, you can add the $29.99 plan which will allow a Bluetooth tethering option for sharing information between your CDMA BlackBerry phone and the BlackBerry PlayBook wirelessly.
Sprint Advanced Technical Support