Drummond not only was an athletic freak, he was a once in a generation type of freakishly atheltic big man. Drummond also was much bigger even as a freshman than what Brimah is right now.
Lastly Drummond played ball all his life, so while he has better hands and better coordination (aka doesn't wind up on the floor frequently after made baskets like Brimah), Brimah picked up basketball relatively late in comparison. Why is that an important distinction? Drummond had some bad habits that are hard to drill out of him (even now as a pro), Brimah is still learning the game so he hasn't had enough time to develop bad habits, therefore every year Brimah spends at the college level he will continue to vastly improve.
For example Brimah does an excellent, excellent job keeping the ball above his head around the rim, as a result he very rarely gets the ball stripped on the offensive end. A lot of big guys like to bring the ball below their waste before going up strong. Brimah keeps it up and that way smaller guards can't come in and swipe it. Brimah is also developing a very nice hook shot, still needs some improvement but has made a lot of progress. Brimah needs more time to work on his hands, he too often bobbles the ball (often playing one man volleyball with himself) and sometimes has a slow reaction to rebounds. With more playing time he can improve in both areas.
In my opinion I think Brimah will likely stay here at UCONN for his junior year if not for his senior year too. He will need the time to grow and will be that much more effective in the NBA after he graduates.