LONDON, England - Formula 1 fans have learned to expect the unexpected and 2012, despite Sebastian Vettel and Red Bull ending up as World champions for the third year in a row, was predictably unpredictable.While Sebastien Loeb racked up a ninth successive championship with Citroen in rallying - an outcome that surprised absolutely nobody - and Audi won Le Mans for the 11th time in 13 years, followers of GP racing had a nail-biting ride right to the end.This was the year of eight different winners, an unprecedented seven of them in the first seven races, from six teams who spent months getting to grips with the Pirelli tyres.RACING ROUND-UPVettel becoming, at 25, the sport's youngest triple champion was an easy prediction to make at the end of 2011 when the German ran away with his second title and Red Bull was dominant.It looked less likely as the sport headed off for its summer break and, after 13 rounds of a record 20-race season, Vettel still had only one win on his score sheet and was 42 points off the lead."People were not even mentioning us when they were talking about the championship, but I think the most important thing was that we always kept believing," the German said after being taken down to the wire in Brazil in a duel with Ferrari's Fernando Alonso.'BY FAR BEST SEASON'Alonso, driving the wheels off an ugly car that had been painfully slow out of the box, was - against all expectations - was comfortably clear of the rest as the championship entered its second half. Even if F1 supremo Bernie Ecclestone held up Vettel as a new benchmark for the sport, team principals voted Alonso their driver of the season and the Spaniard had no doubt about what he had done in a car he knew was not the fastest."It was by far the best season of my career and I will remember this 2012 like some dream season," said the man who won two titles with Renault in 2005 and 2006.The Spaniard's win in rain-hit Malaysia, the second race of the season, was a stunning result considering how far off the pace Ferrari had been in testing and in the Australian opener. He was lucky to escape unhurt after Romain Grosjean's Lotus skimmed past his head in Belgium in an incident that had the Frenchman banned for a race, and Vettel were the main men in a field of six champions - five of them race winners in 2012.SCHUMI AND STONER QUITThere were few gasps of surprise when seven-times World champion Michael Schumacher, three years into an unimpressive comeback with Mercedes and six years on from his last win with Ferrari, decided to call it a day for the second time at the age of 43.There were rather more when 2008 champion Lewis Hamilton cut the umbilical cord with super-successful McLaren and signed for Mercedes, whose otherwise bleak year was illuminated only by the first win as a works team since 1955.That bombshell was comparable to the shock in MotoGP when Australian Casey Stoner announced in May that he was bowing out at the age of 26 because he had fallen out of love with the sport.Spain's Jorge Lorenzo won that title with Yamaha, the second of his career.Hamilton's leaving McLaren for a far less successful team would have been dismissed by many at the end of 2011, and they might have scoffed also at the idea of Venezuelan Pastor Maldonado winning the Spanish GP for Williams - whose chairman Adam Parr had resigned only weeks after being lined up as founder Frank Williams' heir-apparent.FEW BETS ON PEREZHow many would have expected Mercedes to dominate the Chinese GP or for Jenson Button, winning the first and last races of the year, to end up scoring more points than Hamilton over their three-year McLaren partnership? But he did.There would have been few bets on Ferrari academy youngster Sergio Perez ending the season, after the Mexican had celebrated three podium finishes for mid-table Sauber, with a McLaren contract in his pocket.The US returned to the calendar in Austin, the Texan capital that prides itself on being weird and showed it by taking foreign F1 to its heart in a country more enamoured of Nascar and oval-track racing.Some locals were doubtless more interested in Nascar's final weekend at Homestead, which clashed with the Austin race, that saw Brad Keselowski win his first Sprint Cup title with Dodge and denying Jimmie Johnson a sixth championship.American motorsports fans also had an emotional triple winner to acclaim when Scotland's Dario Franchitti triumphed in the Indy 500, a year on from his late friend Dan Wheldon.BERNIE ECCLESTONEBahrain defied international condemnation and put on a race that many had expected to be cancelled due to civil unrest and violent anti-government protests. That race saw the sport's ethics and values questioned on front pages and websites around the world but ultimately troubled Ecclestone far less than a court case in Germany, increasing legal actions elsewhere, and the shelving of advanced plans to float the sport in Singapore.At 82, the British billionaire still had a spring in his step after marrying Brazilian Fabiana Flosi, his 35-year-old third wife.Barcelona, the most predictable race on the calendar, produced a 500-1 winner in Maldonado while Valencia and Abu Dhabi, yawn-fests in the past, turned out to be thrillers. The latter even delivered one of the quotes of the championship from winner Kimi Raikkonen."Leave me alone. I know what I'm doing," the Finn told his Lotus team over the radio as they offered advice he felt he could do without.The sport welcomed its first woman team principal when Monisha Kaltenborn took over the reins from Peter Sauber and shuddered at the freak testing accident that cost Marussia's female Spanish tester Maria de Villota the use of an eye as well as inflicting horrific injuries.BUTTON'S REAL CHANCE?If at the start of the season, the smart money would have been on Vettel and Hamilton fighting for the title with Red Bull's design genius Adrian Newey likely to come out on top, 2013 promises to be different. Even if Vettel again looks the man to beat in a season where the cars will be very similar - if more attractive due to 'modesty panels' allowed to cover up the broken, stepped noses - Hamilton may have to wait until 2014 before he gets a truly competitive car again.That will give Button a real chance as McLaren's most experienced driver, while Alonso can be counted on to fight all the way and Raikkonen will be doing what he knows how to do after an impressive comeback season.Unless, of course, the unexpected happens.