I just visited the sight,and you're right,the enemies do look like the ones in the pics I found!It will be interesting to see what the enemies turn out to be like...I bet the one with the tiki masks is the Uk's version of the Witchdoctor..Also,check out the screenshots of the enemies in the game.
EDIT-Also,I watched the trailor again,and near the end of it,I saw these ships with red and yellow colors on the sails,could these possibly be the Spanish?