The pre-season chatter has ceased in the 2012 Formula One campaign and, already, there are plenty of talking points, following yesterday's opening skirmishes during practice in Melbourne.

Most observers would not have expected the champion, Sebastian Vettel, to be so far down the standings at a soggy Albert Park, and few would have imagined the German driver at the top of the heap would be the veteran, Michael Schumacher. But that is one of the beauties of a new campaign; nearly everything is up for grabs, optimism reigns, and at least half-a-dozen of the field will believe they can go out and win tomorrow's Australian Grand Prix. Here, the Herald explores some of the issues, which will soon become clearer. CAN ANYBODY STOP VETTEL?

We shouldn't read too much into what transpired in yesterday's two sessions, because practice is not necessarily a good indication of competitive form. And yet-Vettel would have been concerned at not finishing higher than 10th and 11th and his words afterwards were those of somebody who knows there is plenty of work for Red Bull to carry out in the next few days. "We have to find the balance and learn a bit more about the car," said the 24 year-old, who is a short-odds favourite to claim his third title in 2012. Roughly translated, that adds up to an admission from the German that he wasn't happy with the performance of his car and his mechanics better get their fingers out. To his credit, Vettel has never believed the hype and repeatedly stated he anticipates a much harder battle this year. He is probably right.

WHAT ABOUT McLAREN'S CHALLENGE?

Lewis Hamilton cut a disconsolate figure 12 months ago, but he and Jenson Button have hit the ground running this time around and the English duo will be confident of challenging for podium places in Melbourne and thereafter on their sojourns to Malaysia and China.

In many respects, this is a more crucial campaign for Hamilton, because his older teammate gained the upper hand, to many people's surprise, throughout 2011, and the pressure is on Lewis to rein in his over-aggressive approach and prove he can amass points without picking up penalties.

Button, for his part, looks relaxed, at ease with himself and his place in his organisation and he possesses the requisite tools to challenge for the main prize this weekend.

WHAT CAN WE EXPECT FROM PAUL DI RESTA?

The Scottish driver faces a different, and potentially more difficult, dynamic at Force India this season. In 2011, he was the rookie, the junior partner to Adrian Sutil, and he emerged at full throttle to wrest the initiative away from his German colleague.

This time, though, Di Resta has to both work with a younger man, in Nico Hulkenberg, who made an immediate impression in Friday's practice, and send out the message that he can pick up points consistently for the course of the whole season. W

We shouldn't fear for the West Lothian man; he is a tough little cookie with boundless amounts of technical mastery and driving ambition. But his tussle with the Hulk promises to be one of the more intriguing sub-plots of 2012.

WILL ANY OF THE NEW BOYS SHINE?

You have to feel sorry for one or two of the lesser luminaries on the F1 grid. As Lester Piggott once remarked: "You can't go anywhere without the horse" and the same applies to those tasked with making the best of a bad job and vying for 18th and 19th every weekend. Jean-Eric Vergne might make a decent impact with Toro Rosso, but one fears for the likes of Charles Pic and Narain Karthikeyan at Marussia and HRT respectively.

The probability is that they will be doing well to finish at most of the venues and that has to be a soul-destroying prospect.

AND WHAT ABOUT THE OLD BOY?

Michael Schumacher still believes, even at 42, that he can genuinely challenge for prizes, podiums and points and yesterday's second session was like a blast from the past, with the seven-time world champion demonstrating that he remains a peerless performer when the conditions turn wet.

Nobody should get carried away, on the evidence of one Freaky Friday. But Schumacher and Nico Rosberg are abrim with confidence, Mercedes appear to have closed the gap on the front-runners, and should definitely improve on last year's lacklustre showing.

DARK HORSE?

Judging from the pre-season wailing at Ferrari, one might have imagined that the Italian motoring giants were in the pits of despair. But there was nothing second-rate about Fernando Alonso's displays in the preliminaries and the Spaniard might actually benefit from being off the radar in the build-up.

He knows what is required to become king of the world and is a relentlessly steely adversary, as Lewis Hamilton will affirm. One suspects he won't be far away and, in common with Vettel, he enjoys No1 billing, so will benefit from Ferrari's expertise in the months ahead.