IDF troops are on the border with Gaza, ready to move in when the air attack let's up.
Also, from jpost.com:
Israel will continue carrying out operations until terrorists in Gaza cry for a cease-fire, Strategic Affairs Minister Moshe Ya'alon said Thursday on Channel 2.
"We will continue until the opposing side says 'enough, we can't take anymore,'" he said. "The IDF has operative plans in place for a [ground operation,] and will use them if necessary."
He added: "All Hamas officials are, like Hassan Nasrallah in Lebanon, hiding in bunkers."