Other video clips:
Corriere della Sera
The official version seems to be that the fellow was mad and that there was no deliberate attempt on the life of His Holiness, the Pope. Looking at the video footage and reading the comments making he rounds of the blogs, I'm not so sure. It sure looked like he was violent and it took quite a number Vatican security guards to tackle the chap to the ground and keep him there. He had also attracted the attention of the guards before jumping, so he must have said something threatening or out of the ordinary. I'm sure it certainly wasn't 'Viva il Papa!'.
I shudder to think what might have happened if the man managed to reach the Pope. The Pope frequently puts himself in danger and compromises his security to let the faithful approach him. Do pray for him, that the Lord who had called him may give him all the necessary graces to sustain him in his ministry as he shepherds Christ's Church on Earth.
Oremus pro Pontifice nostro,
Dominus conservet eum, et vivificet eum, et beatum faciat eum in terra, et non tradat eum in animam inimicorum ejus.
Let us pray for our Pope, Benedict. May the Lord preserve him and give him life, and make him blessed upon the earth, and deliver him not up to the will of his enemies.
H/T to Fr. Tim.