If we are taking presumptions, I would hazard my guess that he's implying the PS4 is the more capable.
I think the general initial sentiment that most developers share before being actually exposed to and working with both consoles, is that both consoles are pretty equal. IMO, This is likely why John Carmack was expressing that both console was similar(I don't belive he's actually dealt with the console other than what he's read that they both contain AMD APUs.)
However, once the developers begin working with both consoles, the difference become apparent.