[Lee Janotta]

Okay, here's my take:

Practice, strategy, and the academic side of driving: Prost made this a very important part of driving, and as the cars have gotten more complex and temperamental, it's become even more important. If you can master this, you'll get far. Not so useful in touring or GT cars. This very technical style is very important, though, on modern tracks with no passing zones, and increases in important in direct relation to the weight of the car, the lighter the better.

Physical condition: Schumacher made this more important than it had been previously, but I refuse to believe it will make the difference between winning and losing. Probably more helpful in front-engined cars.

Natural talent: That raw, seat-of-the-pants feel for exactly what the car is doing at any moment. Most important for rally drivers, it used to be essential for any form of motorsport. Radial tires and aerodynamic improvements which negated 4-wheel drift as a technique for F1 drivers really reduced the important of this, though. Evidence Jean Alesi. Rain is a blessing for these drivers. Typically goes hand-in-hand with...

Drive, dedication, desire to win: There are two kinds; Guys who are out to stock their trophy case, like Schumacher or Mansell, and guys who absolute love to compete, like Montoya, Villeneuve, or Senna. The first can result in some undesirable behavior, but the second is the real stuff. It's what you need to push the car deeper into a corner than anyone else dares, to pass in places you're not supposed to pass... And to make those incredible climbs back through the field after some misfortune. Red haze _really_ pushes a driver and his car beyond their natural limits; evidence Fangio, Nurburgring, 1957.

Mechanical competence: You _have_ to be able to work with your engineers to get the setup you want, and during the off-season, craft a car suited to your strengths, or to compensate for your weaknesses. You'll never be a #1 driver without some measure of this. I'll have to admit, M. Schumacher seems very good at it.

I'm gonna try and break down some current top contenders here. Just off the cuff...

M. Schumacher, wins the race before the lights go out
Technical: 35%
Physical: 10%
Talent: 30%
Desire: 5% (he's done some damn stupid stuff to win, but no red haze)
Mechanical: 20%

J. P. Montoya, driving by the seat of his pants
Technical: 15%
Physical: 0%
Talent: 60%
Desire: 20%
Mechanical: 5%

R. Schumacher, precise and practiced, doesn't take risks
Technical: 65%
Physical: 5%
Talent: 20%
Desire: 0%
Mechanical: 10%

K. Raikonnen, extremely well balanced
Technical: 35%
Physical: 10%
Talent: 35%
Desire: 10%
Mechanical: 0%, but he's very young

Mind you, in the real world, this shouldn't always add up to 100. I'd put Montoya and M. Schumacher at 100 based on today's scale, Kimi at 95, and Ralph at 90. And of course, that varies with how a given track suits them.