The Facebook invite page already has a thousand people who say they will attend.
It appears that this is being organized by theIslamic Action Front, a branch of the Muslim Brotherhood, which is obliquely warning that any actions by Jordanian authorities to stop them will indicate their collusion with the hated Zionists and will result in their fall.
Meanwhile, the official Egyptian news agency reported that Israel's embassy in Jordan was reinforcing security measures. Eye-witnesses claimed that they saw armored vehicles and a large number of security forces on the streets leading to the embassy.(h/t Dan)