His debut promo was quite impressive. The way he spoke was almost perfect (neither too fast nor too slow). As PaperGhost pointed out his facial expressions were great. His gimmick seems to be really different from the usual cocky heels that are present in abundance. I have not seen his ring work, so can't comment on that.
He does seem like a guy that could be a really impressive mis-card heel and if he gets good reaction, could be pushed to the main event status. I hope that the WWE builds him up stedily instead of pushing him to the main-event right away.