No Way! If he lifts the left arm up to fend off defenders then its an offensive foul. He is 7'5" he does not need to use his arm to fend of defenders.
How SWEEEEEEEET it is, Rockets win 15th straight- Gene Perterson! Im so excited about the season, I cant wait,
Aaaaaaaaaa dude, he won't be playing against 6'6 centers in the NBA dude, so I don't think he'll have the same height advantage in the real games dude, and if you've ever seen a NBA game dude you'd notice that they all fend off defenders with that other arm dude. Check out pics of the hook shot master Kareem, you'll notice that left arm was out 2-3 feet on every one.
You can use your left arm to defend your space, but you aren't supposed to bring it into the defenders space to hold him down or push him back. Unless of course your name is Shaq, then your off arm is allowed to be in your defenders grill as long as you only bump him back 4 to 6 feet. Then Burger King marketing execs are happy, NBC is happy. Hell the whole free whorld is happy.