Hi,
There will be an upgrade procedure from 6.0 (SP1) to 7.0 available during October.
The last statement from our CTO is in the discussion under
Kentico CMS 7 Final full feature list blogpost:
Upgrade from v7 RC to final should be available at the beginning of October (probably released at the Prague Connection), and upgrade from v6 to v7 later in October (probably second half).In the meantime, you could use export - import scenario.
As for the license keys - Yes, version 7 requires new license key (as every major version). It should be possible to upgrade your keys in the Client portal
Keys section, or, please, send us an email to support@kentico.com.
Please let me know if I can be of any further help.
Regards,
Zdenek