The author's thesis is that Israel was using the Arab refugees as a bargaining chip in getting Jews out of Arab countries. Of course, this never happened, so the author's analysis is wrong, but the facts that he mentions surrounding the Arab refugees seem to be on target.
United Press' Robert Miller says explicitly that the Jews bent over backwards to stop the Arabs from fleeing ("the greatest concessions were made to the Arabs if they would remain in Jewish territory...The Arabs refused to listen.")
And then, he says that Israel started encouraging the Arabs to flee (he got the reasons wrong, as mentioned above.) But what is the worst that the Jews did?
"They pointed out that the Arabs were welcome to remain, but that the Jews couldn't furnish food. The Jews offered to provide trucks to take the Arabs to the front lines."
Here is the Israeli crime, as of August 1948: telling Arabs that if they wanted to leave, they would help them.
The article does not spell out why the Arabs left, whether it was out of fear or because they were encouraged to, but it does say explicitly that Jews did not force Arabs out of their homes. Not that this never happened - in the course of a war bad things happen and things are always a lot more muddled while they are happening. But so far I have found no contemporaneous evidence of it, although there were plenty of accusations to that effect by the Arab leaders at the time as they tried to demonize the Jews while they grappled with the undeniably huge refugee problem that was dropped on the doorsteps of Syria, Lebanon, Jordan and Egypt.
Interestingly, Saudi Arabia refused to accept any Arab refugees, claiming that they had no money for them, but offered to pay for fighting Jews: