Israel will need them close to the border with Hezballistan, and close to the border with Hamastan. However, there is the possibility that Egypt, in this transitional time, won't have the capability or the clarity to avoid Iranian, Hizballah, Hamas or Al-Qaida penetration of the Sinai peninsula, and batteries defending the Negev may become necessary as well. I disagree with both schools of thought: the one that mantains that defensive batteries are too costly, and the other, that deterrence must not be defensive. Both are unrealistic. The sad truth is Israel sorely needs to seal it's airspace for short, medium and long range missiles, rockets or katyushas at whatever cost. The instability all around and the explicit threats are evident.
Official: Top Burundi general assassinated in the capital (AP)
from the article: Iron Dome missile defense system to become operational within weeks