Canada has always been 'one of thse tracks' where you get lots of incidents. I think what made Kubica's accident realy bad, was the fact that his front wheels never hit the ground before he hit the wall, so there wasn't much in the line of braking resistance going on. And the angle that he hit the wall too was very reminiscent of Sennas fatal crash. Other than that the rest of the accident was fairly tame, with just bits of car flying everywhere, which makes it 'look' more spectacular.
But F1 has done well recently, without any major crashes for a while.
The reason the FIA moan about silverstone, is because of the pit facilities are not exactly up to scratch, for some reason, and need updating. But I think they are putting a lot of money into it to bring it up to standard.
It'd be nice to see the GP return to Donnington again.