There are some glaring flaws in his game on the defensive end of the floor, though I believe that they can be overcome at the next level. Parker may never be a shut-down perimeter defender, though he can most certainly be a part of a great defensive system that relies on the defense as a whole to succeed (see: Spurs, San Antonio).
This game highlights some of the best things he can bring to the floor for the Cavs though. Parker brings one of the best mid-range games that I've ever seen at the college level, not to mention long distance range and moves around the basket that will allow him to post up. Furthermore, this tape highlights the athleticism that he has. While Parker might not hit his head on the backboard like Wiggins may, he's more than capable of finishing high and strong. You can also see an inherent knowledge of where he needs to be on the floor off the ball in order to create easy baskets.
If you need any more reasons to draft Parker, listen to this interview done with Basketballinsiders.com's Steve Kyler on 92.3 the Fan:
Interview with Steve Kyler
Alright. I'm done gushing. Watch the video and see for yourself.