|World Cup finalists France will be hoping to stamp their claim on the northern hemisphere title [GETTY]
With four different champions in the past four seasons and no overwhelming favourite, the 2012 Six Nations could be the most open and interesting tournament for years.
Three of the six teams have switched coaches since last year's Rugby World Cup, several stalwarts have retired and there are questions to be answered over the next six weeks.
Can Philippe Saint-Andre fine-tune a France squad that defied expectations to reach last year's Rugby World Cup final or will interim England coach Stuart Lancaster engineer a successful title defence with an exciting but inexperienced squad?
Perhaps Wales can build on fourth place at the World Cup, or maybe Ireland's injection of youth is exactly what their experienced squad needs.
With Wales hit by injuries to flyhalf Rhys Priestland and prop Gethin Jenkins, France and Ireland appear to be best placed to contest the title.
Saint-Andre has picked largely the same squad that lost the World Cup final by a single point even with the players and his predecessor, Mark Lievremont, barely on speaking terms. With the coach and players pulling together, the title is a realistic prospect.
The presence of IRB player of the year Thierry Dusautoir and Imanol Harinordoquy means that Saint-Andre, who recalled prop David Attoub a year after his 52-week ban for gouging expired, can rely upon the strong pack he - and France - traditionally favour.
"It's true that rugby since professionalism, teams are fitter, much more analysed and it's more and more difficult to score tries from 100 metres - but I think it's still possible,'' Saint-Andre said.
"For the France team, what is very important is a good base.
"We need to play first with a good foundation and then we'll see.''
There will be no repeat of Lievremont's experimental use of scrumhalf Morgan Parra at flyhalf as Francois Trinh-Duc will start in that position in Saturday's competition opener against Italy.
Italy beat France in the Six Nations for the first time last season, but Nick Mallett's replacement as coach by Jacques Brunel is unlikely to herald much change in Italy's approach or fortunes.
Former France assistant Brunel wants to introduce a more expansive style, but the muscle of No. 8 Sergio Parisse and prop Martin Castrogiovanni is still Italy's most potent weapon.
"I think we can even win the tournament in two or three seasons,'' Brunel said of his new side.
"But we have to learn to do more in so many aspects: more speed, more intensity, more discipline.''
Italy will play at the larger Olympic Stadium in Rome this season, giving them the lift of about 70,000 fans for matches against England and Scotland.
The tone of Scotland's campaign could be defined by what happens in the opener against England at Murrayfield.
Victory over England could galvanise a squad missing the reliable boot of the retired Chris Paterson to retirement and captain Kelly Brown to a leg injury. Defeat in one of their two home matches could leave the Scots, led by hooker Ross Ford, facing another tussle with Italy to avoid last place and the so-called wooden spoon.
If Scotland needed any more motivation to wrest back the Calcutta Cup from their oldest and fiercest rival, there is the fact that England edged them to a place in the World Cup quarter-finals only with a 77th-minute try from Chris Ashton in the teams' final pool game.
"You use every emotion. That is what rugby's about. It's an emotional game, a passionate game, a physical game, and you've got to channel all that into your performance. "
- Scotland coach Andy Robinson
"You use every emotion,'' Scotland coach Andy Robinson said.
"That is what rugby's about. It's an emotional game, a passionate game, a physical game, and you've got to channel all that into your performance.''
With Robinson among those to accuse England players of arrogance for their behaviour at the World Cup, Lancaster wants to overhaul his team's image and mentality just as much as he does its performances and style of play.
"There's a lot of people with opinions,'' Lancaster said.
"The opinions that matter to me are those of the players, the management team and the people surrounding the team.
"We want to be known as a humble, honest, grafting team. We want to make sure spectators feel excited watching us and feel connected to us.''
With Jonny Wilkinson and Steve Thompson retired from international rugby and Mike Tindall no longer in the squad, England's final links to the 2003 World Cup-winning team have been broken.
Instead, Lancaster has given youth their head and - in something of a gamble - given the armband to flanker Chris Robshaw, a veteran of one cap.
There will also be a new-look backline that is set to contain the highly rated Owen Farrell, who England fans hope will eventually end up being Wilkinson's natural replacement at flyhalf.
Without captain and inspirational centre Brian O'Driscoll, Ireland look a less fearsome prospect but their hardened pack of forwards will be a match for anyone, especially in their three matches at Dublin.
The Irish are still haunted by their failure to turn up in the quarter-final loss to Wales at the World Cup. For that reason, the visit of the Welsh to Lansdowne Road is a perfect opening match.
"The mistakes that happened in the World Cup won't happen in this game,'' Ireland centre Gordon D'Arcy said.
|Wales face an injury crisis before the tournament has even started [GETTY]
Of all the northern hemisphere teams at the World Cup, Wales were the most impressive and would likely have gone on to beat France in the semi-finals had captain Sam Warburton not been sent off in the first half.
Yet, a series of untimely injuries has threatened to derail their campaign before it has even begun.
Jenkins joined the first-choice lock pairing of Alun Wyn Jones and Luke Charteris on the sidelines, while Priestland, Jamie Roberts and Dan Lydiate are all nursing injuries.
Without the retired Shane Williams, coach Warren Gatland will be hoping fellow winger George North can continue his sensational start to his international career.
Gatland, like many others, predicts a wide-open competition.
"Any one of the six teams have potentially got a chance of winning this competition, which I think is great for the tournament,'' he said.
"A few years ago, everyone was talking about England and France all the time and everyone else was making up the numbers. That's not the case now."