They've probably been begging Barry to do Osama in ever since he took office. I have no doubt that if people have been watching that house for years someone leaked it to the Saudis. They wouldn't care to be as careful as we might be, they'd want us to demolish the place just on the chance Osama was there.
While at one time they said just ignore him since he was ill and couldn't live all that long anyway, since mid-2007 they've had an increasing number of problems in the Kingdom and it can be tracked right back to Osama. At one point they figured Barry for a friend, but found out that in spite of his bending over and offering their King a BJ when they met, he is really only a friend to himself.
JMHO based on what some friends who have been working over there have said.
It makes sense that what finally got Osama was all the uprisings.