It's something he describes as an "entirely new experience" in an interview with Destructoid, explaining that it is not simply a case of a "few extra levels".
According to Tameem, the additional content was designed as a whole new project with "extra time and budget". Namco's previously mentioned that the DLC will include Enslaved's "Pigsy" character, but Tameem wouldn't confirm that.
Enslaved's due out next week. We're pretty stoked for it.