Ferrari are the form horses but don't write off old Michael

There are so many significant changes to Formula One for the new season that it is difficult to know where to start when it comes to calculating likely form.

First of all, there is the return of Michael Schumacher, who at 41 is as fit and focused as when he won 92 grands prix and seven world titles, and the metamorphosis of the remarkable double title-winning Brawn team into Mercedes' own pukka Silver Arrows equipe.

Jenson Button is settled alongside Lewis Hamilton at McLaren and will be determined to prove that the 2008 champion will not have an easy time with him.

Then there's Fernando Alonso adding fresh impetus to Ferrari while Felipe Massa returns as healthy and determined as ever after his accident in Hungary last July. And Sebastian Vettel and Mark Webber are also ready to go mano a mano at Red Bull, where owner Dietrich Mateschitz expects them to deliver a title.

Small wonder it's being touted as the most exciting season for the World Champion-ship in years, even though sponsorship has never been harder to acquire, as many of the new teams have discovered. US F1 failed to make it for 2010 but are hopeful for 2011.

There will still be three new teams – Lotus, Hispania Racing and Virgin – and five rookie drivers – Nico Hulkenberg, Vitaly Petrov, Karun Chandhok, Bruno Senna and Lucas di Grassi. Like Lotus and Cosworth, Senna brings a famous name back into the top echelon. And the Russian Petrov and Indian Chandhok are expanding the sport's demographic as it prepares for a race in South Korea towards the end of the season. They are important developments in such difficult times, as Russia and India are significant markets that are likely to become bigger F1 players in future. But all the newcomers/returnees must justify their inclusion with solid performances.

The rules haven't changed much. The most significant is the ban on refuelling, obliging teams to develop longer- wheelbase cars with up to 160kg of fuel-tank capacity instead of the previous 80kg, and to rearrange weight distribution. The ban will place a premium on drivers preserving the Bridgestone tyres between their mandatory stops – which will be lightning fast – in which they must now only switch compounds.

"Even a small slide, if you push too hard trying to make a move on somebody who is preserving their rubber in the early laps, can be enough to ruin your tyres for the whole stint," Button has warned.

It will change strategy and promote greater efforts to overtake too, as there will be less potential for drivers to wait for pit stops to make up places.

There's also a significant change to the scoring, with a much greater reward for winning. Points now run down to 10th place: 25-18-15-12-10-8-6-4-2-1.

So who will win? Race pace will be more important than qualifying pace, and the indications from testing are that McLaren, Ferrari, Red Bull and Mercedes are closely matched, but that Force India, Williams and Sauber could spring big surprises.

Is it possible Schumacher could harvest all Mercedes' major points, while Button and Hamilton, Alonso and Massa and Vettel and Webber steal them from one another?