I don't think it's really a matter of being cocky , Microsoft are trying to convince their stakeholders, customers and every other relevant stakeholder that the XBOX 360 is still in a strong position .
I mean come on what would you say if microsoft said " Oh shit the PS3 catching up with us we're not sure wether we're gonna come 3rd this gen or not" This is competition and anything other than "cocky"ness is admiting defeat.