How quickly things change in Formula1. Before the Brazilian GP, it was thought that Ferrari and Michael Schumacher were already planning their world championship celebrations sometime mid season!. Following Brazil, the situation appears a lot different.
Not only did Ferrari falter in Brazil but the points went to their immediate rivals with David Coulthard now just 6 points behind Michael Schumacher in the drivers championship. But the real threat in Brazil was from Williams. A 2nd and 4th place qualifying from Ralf and Juan Pablo confirmed that Ralf's qualifying form in Malaysia was not a once in a lifetime achievement. Then the even bigger surprise when Juan Pablo overtakes Michael Schumacher's lighter on fuel car on only the second lap of the race. 
The only concern for Williams appears to be these rear end shunts which are hopefully just bad luck.

All the teams (except Minardi) conducting testing last week at one of 4 venues. All the teams were running two separate programs, one concentrating on traction control for Spain while the other was on setup for San Marino.

Last year Michael Schumacher won the San Marino GP through the pits ahead of Mika Hakkinen. David Coulthard finished 3rd after passing Rubens Barrichello via the pits too. Will the new limitations on aerodynamics and the grippier tyres make overtaking easier ?

Ferrari: Perhaps not winning in Brazil will have a positive effect on them. In the end though Michael finished 2nd and that is not a bad result. What will be worrying them is the power of the BMW engine. On high speed circuits they might not have a chance.

Reliability 8.5/10 - Speed 9.0/10

Drivers: Michael Schumacher will have to fight with a number of contenders including David Coulthard, Mika Hakkinen, Ralf Schumacher and Juan Pablo Montoya. The pressure will be on but if his car is performing well then he could win with a podium at the least.

Rubens Barrichello never did well in Brazil so he should not be judged by his form over there. Driving at his home GP could put a lot of pressure on him. However his over aggressive style is a cause of concern and if that doesn't stop he'll be banned. He will probably drive a conservative race in San Marino just to get the attention away from him. A top 6 finish is possible if he doesn't crash into someone!

McLaren: Appear to have made significant progress in Brazil and are closer to Ferrari. They claim that they will improve more in time for San Marino. Does this mean that they will be stronger than Ferrari ? 

Reliability 6.5/10 - Speed 8.5/10

Drivers: Mika Hakkinen, 1 point from 3 races is not a good start. It appears that this year gremlins are hitting his car rather than Coulthards. Still if the reliability is sorted out, he will be a tough opponent to both David Coulthard and Michael Schumacher. A win is possible.

David Coulthard has been very consistent so far this year. Like Michael Schumacher, he is the only other driver to finish on the podium in every race so far this year. If the McLaren delivers the promised goods then a win is very possible.

Jordan: Honda appears to lack power compared to BMW, Ferrari and Mercedes and that affects both Jordan and BAR. Jordan also have reliability problems with the gearbox and clutch. Heinz Harald Frentzen retired from 3rd in Brazil. They appear faster than BAR but less reliable.

Reliability 6.5/10 - Speed 8.0/10

Drivers: Heinz Harald Frentzen Lost 3rd place in Brazil due to a car failure. He is a very consistent driver and if his car doesn't fail him and a number of drivers ahead of him drop out he can finish on the podium or in the points at least.

Jarno Trulli could be faster than Frentzen on a single lap but is not as consistent. If his car delivers and he is consistent then he'll beat Frentzen otherwise he'll be a few places behind.

Sauber: Have the amazing ability to just be there when the rest fails. Who would have predicted a podium finish for them in Brazil. Well they did and had Raikkonen not spun in Brazil they would have both drivers in the points.  

Reliability 8.0/10 - Speed 7.5/10

Drivers: Nick Heidfeld drove very well in Brazil and managed to finish on the podium. Unless a similar situation happens here, it is unlikely that he'll finish on the podium or even in the points. 

Kimi Raikkonen After his superb debut in Australia, he has failed to finish in the following 2 races. He needs to be more consistent but given his lack of experience, that is expected. A top 10 finish is possible. 

BAR: They appear to be slower than Jordan especially in qualifying. Villeneuve and Panis were on a blistering pace at Silverstone last week in testing so they could have found a few improvements on the chassis side.  

Reliability 8.0/10 - Speed 7.5/10

Drivers: Jacques Villeneuve had a problem with his car in Brazil robbing him of a potential point finish. He still finished in 7th place which is something that he needed to do after failing to finish the first two races of the season. A finish in the points is possible.

Olivier Panis Out-qualified and outraced his team-mate in Brazil and that must give him even more confidence. A BAR pit stop mixup in Brazil cost him a podium finish. If BAR give him a good car he should also finish in the points. 

Williams: It is a shame that they only have 2 points so far. They have been having the problem of other cars crashing into them and what can they do about that ? It appears that they have the most powerful engine and combine that with a good chassis and 2 very good drivers and you end up winning races.

Reliability 7.5/10 - Speed 9.5/10

Drivers: Ralf Schumacher was practically eliminated from the Brazilian GP by Barrichello, but Williams managed to get him back out and he set the fastest lap of the race until he spun out raising a potential weakness with the Michelin wet weather tyres. A win is possible here if the car doesn't fail.

Juan Pablo Montoya has proven his worth in only his third race. Passing Michael Schumacher with a heavier fuel load just gives him more motivation to do even better. He could have won in Brazil and he could win here. Overtaking is a problem in San Marino and it will be interesting to see how Montoya handles that.

Benetton: They scored a point in Brazil and given their lack of pace, that was an achievement. They will be praying for more races where a lot of cars ahead will retire. Otherwise they won't shape.

Reliability 7.0/10 - Speed 5/10 

Drivers: Giancarlo Fisichella managed to score a point in Brazil. He is unlikely to repeat that again soon this season. Even a top 10 finish is unlikely and that is not due to his skill but his car.

Jenson Button is in the same boat as Fisichella, even a top 10 finish is unlikely unless a lot of cars ahead fail.. 

Arrows: They are struggling at the back with Benetton and Minardi. The AsiaTech engine is not helping. They need improvements fast otherwise they will be another Minardi.  

Reliability 7.5/10 - Speed 5.5/10

Drivers: Jos Verstappen had a nightmare when he crashed into Montoya. His performance in Malaysia was overshadowed by what he did in Brazil. He should recover but his car isn't good enough to get him a top 10 finish. 

Enrique Bernoldi managed to outqualify his team-mate in Brazil which was a surprise. He retired with a car failure. A finish inside the top 10 is unlikely. 

Jaguar: Their reliability didn't turn out to be that much improved. Both cars failed in Brazil and one must wonder when Jaguar will start getting it right. It doesn't look like this year! 

Reliability 7.0/10 - Speed 6.5/10

Drivers: Eddie Irvine retired in the last 2 races due to spins in the wet. He'll need to start performing otherwise he'll be the one to be replaced by de la Rosa next year. A top 10 finish is possible if he keeps it together and Jaguar give him a reliable car.

Luciano Burti retired in Brazil due to an engine failure. He appears to be consistent during races so he might finish in the top 10 ahead of his team-mate.

Prost: Should be doing much better than this. Running the same engines as Sauber, they should have scored a point or two but so far they are not even close.

Reliability 6.5/10 - Speed 6.0/10

Drivers: Jean Alesi's struggle in Brazil in the wet was possibly due to the Michelin tyres. Wet weather is Alesi's only hope of finishing in the points.

Gaston Mazzacane was 21st in Brazil no wonder why there is talk that Prost wants to replace him. 
A finish in San Marino is possible a few laps down though.

Minardi: Given their limited budget and resources, they are doing better than some other teams

Reliability 6.5/10 - Speed 4.5/10

Drivers: Fernando Alonso managed to qualify in 19th place in Brazil but had a car failure. He has potential to become a future champion and another team will be offering him a drive soon. A finish here is possible.

Tarso Marques qualified 22nd and was almost the last car to cross the line in Brazil. Don't expect any better in San Marino.