Although I am new here, I must disagree in some points here.
Formula 1 did some major changes in their rules, to make overtaking more possible.
i.e KERS which already been abandoned though, but the most major changes happened in tyres, and aerodynamics.
So that the car behind you can drive closer, without loosing too much grip.
And yes, Senna was the best driver ever, I have to agree.
By the way, did anybody happened to see what happened to Massa. Talking about bad luck...