Another weakness of the movie for me was the way they baited Silva to go to Skyfall. If Q's breadcrumbs are so convincing that Silva storms the home by that night, why not place M in a safehouse ten miles away and allow Bond to take care of business without any risk to M? Silva was obviously convinced that M was there, so what was the point of risking her life and eventually killing her?
It's the classic trap seen in Return of the Jedi, where the Emperor fools the rebels to attack the death star by giving them the... actual weaknesses to his battle station. Why not tell the rebels that the shield generator is on the other side of Endor? That way, the rebels attack, and there is 0% risk that the death star is harmed. Bleh.
/Rant Ovah
You're aware this is a Bond movie, right? This is the same series that cast Denise Richards as a nuclear physicist and gave us Grace Jones as a girl baddie.