Four world champions are in the field - the reigning Jenson Button, who has joined 2008 champion Lewis Hamilton at the McLaren-Mercedes team, Spain's dual champion Fernando Alonso, now with Ferrari, and the returning seven-time "king", Michael Schumacher.

Three years older, at 41, after three seasons out of grand prix racing, Schumacher joins the Mercedes team that last year was the victorious BrawnGP and before that Honda's team.

Schumacher says he feels like a kid looking forward to Christmas. To an older, admittedly cynical, mind he's like an addict who can't get by without the drug, or a boxer going around once too often.

The winner of 91 GPs, 40 more than next best Alain Prost, what more can the German achieve?

Perhaps he will win races. Maybe even an eighth title. But more likely he will end up diminishing his standing, even if only a little.

The reality is that the pool of driving talent in F1 now is deeper than in Schumacher's previous 14 seasons.

Alonso beat him fair and square in 2005 and '06. Before that his only serious rivals were Mika Hakkinen and Jacques Villeneuve.

For the first time the Schu will encounter the young black Brit, Hamilton, who took only two years to become world champion - and almost did it in his first season.

An even bigger worry for him may be fellow German Sebastian Vettel, teammate to Australia's Mark Webber at Red Bull Racing.

Already the winner of five GPs at just 22, Vettel is seen as the driver most likely to ascend to the throne next, perhaps this year. But for a couple of glitches he may have overhauled Button last season.

There are others. Felipe Massa, who was on L plates in Schumacher's final days at Ferrari, is back, totally recovered from a nasty eye injury last year. Poland's Robert Kubica too, although he is in a Renault team seemingly on the slide. And Webber, a two-time GP winner now, hungry for more and in perhaps the best team of the moment. Yet Schumacher's biggest headache may be his teammate, Nico Rosberg, son of 1982 world champion Keke and who has served his apprenticeship with the Williams team and may be ready to blossom in the team now representing the world's most prestigious mass car maker.

This season sees the arrival of three new teams. It should have been four, but USF1 has failed ignominiously to make it.

The great F1 name Lotus is reborn under Malaysian ownership, Sir Richard Branson splashes his Virgin brand on a British newcomer that is really Manor Motorsport, and Hispania Racing - born as Campos Meta by Spain's former Minardi racer Adrian Campos but already transformed - arrives from the Iberian peninsula with two rookie drivers. They are Brazilian Bruno Senna and Indian Karun Chandok, who gets his baptism a year ahead of his country hosting its first GP.

Triple world champion Ayrton Senna, still widely regarded - more than 15 years after his death - as better even than Schumacher, once said: "If you think I'm good, wait until you see my nephew."

The kid was then only a go-karter in short pants. His first F1 car hasn't even turned a wheel yet, and in any case it is unlikely to let him do much other than upstage his teammate.

The best of the new boys is likely to be another German, Nico Hulkenberg, with Williams, where veteran Rubens Barrichello will be his teammate and benchmark.

Schumacher's long-time manager, Willi Weber, is concentrating his energies on Hulkenberg now as the headline writers salivate at the prospect of an "Incredible Hulk" in F1.

To the untrained eye this year's cars will look as odd or ugly as they have for years, since the rules that have made them so much safer have equally sapped the designs of the creativity of the 1970s and '80s.

The main difference is that they are longer, to house bigger fuel tanks - as refueling during races is now banned.

Drivers will still stop for compulsory tyre changes. Without taking on fuel, they may be stationary as little as four seconds.

Despite the departure of manufacturers Honda, BMW and Toyota in the past 15 months, there are 12 teams now, instead of 10.

The scoring system has changed, with 25 points for a win this season, 18 for second, 15 for third, while the next seven finishers get 12, 10, 8, 6, 4, 2 and 1.

It's the same for the rallying and touring car world championships now, incidentally.

Bahrain may seem an odd starting point for the premier motor racing series, but it makes some sense. The live telecast of its GP was the most watched of all F1 races last year.

And, according to London research firm Initiative, futures sport + entertainment, it was the third most watched live sports telecast of '09, behind only the UEFA football final and America's Superbowl.

Apart from the four champions on the grid, all 20 retired but living F1 world champions have been invited to Bahrain for the 60^th birthday.

Australia's Sir Jack Brabham and Alan Jones are among those being flown in first class, with chauffeurs waiting and red carpet assured all weekend.

It will be a far cry from last year's season starter in Melbourne, when Brabham and Jones stayed home, feeling unappreciated by the Melbourne organisers.

Australian Grand Prix Corporation chief executive Drew Ward has been quoted saying ticket sales for Melbourne's March 25-28 event are up 20 per cent, on the back of Schumacher's comeback.

If correct, that would be 20 per cent up on the depths of last year, when the AGPC reported its second straight loss of $40 million on the F1 race.

With this year's race now less than three weeks away, the building of the temporary grandstands and corporate facilities at Albert Park does not reflect any such increase.

The Fangio grandstand on the pit straight is barely half the size it was years ago, and there are no signs of a corporate marquee between the circuit's fifth and 14^th corners - where dozens once were erected.

Schumacher may wonder, when he ventures out for his first practice lap in Melbourne on Friday, March 26, whether - without the wall of white marquees behind the safety fencing on the lake side - he's on the same track he has circulated perhaps 1000 times before.

A year-long search for a naming rights sponsor proved fruitless - with no takers at $3 million, 60 per cent of the annual fee years earlier - but Qantas came to a face-saving rescue in late February, although it will have been at a distress price.

As the Melbourne media speculates about a $50 million loss on this month's race, moves are afoot to move the GP to a permanent circuit, with trucking tycoon Lindsay Fox's Linfox company volunteering to bankroll a track at Avalon, beside its airport near Geelong.

It would be much further for high-rolling international visitors to trek from Melbourne's swankest hotels, but it could be a way of F1's elderly emperor Bernie Ecclestone getting his wish of a night-time Oz GP to garner a bigger European TV audience.

But any move won't be before the expiry of the existing contract in 2015, if ever.

In the meantime, the one thing that might give Melbourne's GP a rev-up this year, more than Schumacher's comeback, is if Webber can qualify on the front row at Albert Park with a real show of winning his home race.

Even then, even if Webber were to pull off a fairytale victory, it won't make the financial picture after the chequered flag any brighter.