Germany are one of the big favourites and I think they are the only European team other than Spain who can win the World Cup next summer.
German club football is on a high and producing top-class talent. The national team's attacking midfield options are incredible.
But conditions are different in South America: the grass is longer and thicker, and the heat and humidity can be an issue.
Like all of the European teams, Germany will need to adapt quickly to excel.
How do they play?
Style & formation: Blessed with far more flair than many Germany sides of the past, their fluid 4-2-3-1 is underpinned by Bastian Schweinsteiger and the currently injured Sami Khedira anchoring the side from the base of midfield.
Ahead of them lies creative fulcrum Mesut Ozil, who is usually flanked by the dangerous Marco Reus and Thomas Muller.
Strengths: They have cover in virtually every position and an extraordinary variety of forward-thinking midfielders.
Try picking three from Ozil, Reus, Muller, Andre Schurrle, Julian Draxler, Mario Goetze, Toni Kroos, Sidney Sam and Lukas Podolski.
Weaknesses: German teams traditionally have a reliable defence but the current one has creaked of late and they conceded seven goals in two qualifiers against Sweden.
Per Mertesacker is approaching 100 caps but he has a perceived lack of pace and can be vulnerable to balls over the top.
The evergreen Miroslav Klose is just one goal shy of Ronaldo's all-time World Cup finals tally of 15, but he will be 36 by the time the tournament starts and a reliable replacement has yet to be found.
Key player: Bastian Schweinsteiger
Bastian Schweinsteiger's glittering CV has one glaring omission - international silverware - and it's something the 29-year-old is desperate to rectify.
The winger-turned-central midfielder has been described as the "brain" of the national team by coach Joachim Low, and he is no less influential at Bayern Munich.
One to watch
Earmarked for greatness, Julian Draxler became Schalke's youngest-ever player when he made his debut aged 17 back in 2011. Just over a year later, the gifted playmaker was called up to the preliminary senior squad for Euro 2012. Ten Bundesliga goals last season shows why Arsenal are reportedly interested.
The boss
At the helm since 2006, Joachim Low signed a new contract until 2016 earlier this year but the pressure is on to win a trophy after some agonising near misses. His win percentage of 68% is the highest of any Germany manager.
How they qualified
Germany breezed through their qualifying group, only dropping points in a bizarre 4-4 draw with Sweden - having led 4-0. They scored 36 times in 10 matches, with seven of their attacking players totalling three goals or more.
World Cup record
Germany have reached the final seven times, winning for the third time in 1990.
Runners-up in 2002, they were third in 2006 and 2010.
Fifa ranking: 2
PORTUGAL
Prospects
It would be disingenuous to say Portugal are a one-man team, but realistically the form and fitness of Cristiano Ronaldo will determine how far they advance.
His brilliance masks the continued lack of a top-class conventional striker and there have been too many laboured team displays since they were beaten on penalties by Spain in their Euro 2012 semi-final.
Key player: Cristiano Ronaldo
It can only be Ronaldo. Now 28, he is at the peak of his considerable powers - a supreme athlete and exquisite technician who has so far scored 67 goals in 56 games for club and country this calendar year.
Fifa president Sepp Blatter recently claimed Ronaldo "spends more time at the hairdresser" when asked to compare him with Lionel Messi, but it is the Portuguese who is expected to be recognised as the world's best player of the year at the Ballon d'Or ceremony in January.
The boss
Paulo Bento took charge in September 2010, 10 months after resigning from Sporting Lisbon, where he won four domestic cups in six years.
Bento, who played at the 2002 World Cup, inherited a Portugal side bottom of their Euro 2012 qualifying group but he swiftly restored harmony and improved results.
How they qualified
They progressed via the play-offs for the second successive World Cup, with Ronaldo's hat-trick against Sweden equalling Pauleta's national record 47-goal tally.
They only lost to Russia in their group but finished second after drawing with Northern Ireland and Israel, twice.
World Cup record
Portugal are heading to their sixth World Cup. They came third on their debut in 1966 and were also semi-finalists in 2006. Three years ago, they lost to eventual champions Spain in the last 16.
Fifa ranking: 5
GHANA
Prospects
On the face of it, Ghana are one of the strongest African sides. Semi-finalists at each of the last four Africa Cup of Nations, only a cynical Luis Suarez handball prevented them from reaching the same stage at the 2010 World Cup.
They were significantly strengthened during the latter stages of the 2014 qualifying campaign by the return from self-imposed exile of brothers Andre and Jordan Ayew, Michael Essien and Kevin-Prince Boateng.
Keeping that quartet on board will be vital.
Key player: Asamoah Gyan
Former Sunderland striker Asamoah Gyan, 28, continues to lead from the front for Ghana.
His six goals in as many qualifying appearances all came from open play and he averages more than a goal per game for his club side Al Ain in the United Arab Emirates.
The boss
Former Ghana captain James Kwesi Appiah, 53, was promoted to head coach in April 2012 after four years as assistant and occasional caretaker boss.
Softly-spoken and unassuming, he was not initially a popular - or suitably high profile - appointment with many fans but he has now become the first Ghanaian to lead the nation to the World Cup finals.
How they qualified
Having won their group with five wins out of six, Ghana thrashed Egypt 6-1 in the home leg of their play-off to ensure a 2-1 loss in the return leg was academic.
They ended as the top scorers in African qualifying with 25 goals.
World Cup record
In 2010, Ghana seemed certain to become the first African semi-finalists after Uruguay's Luis Suarez was sent off for handling on the line in the dying seconds of extra-time. However, Gyan missed the spot-kick and Ghana then lost the penalty shootout.
Brazil will be their third successive finals, having first qualified in 2006 when they went on to reach the last 16.
Fifa ranking: 24
USA
Prospects
Head coach Jurgen Klinsmann says the minimum aim is to reach the knockout stage, and a national record 16 wins in this calendar year - including against an admittedly depleted Germany - gives cause for confidence.
Defence is a concern and then there's the lack of continuity - 37 players were used in qualifying.
Clint Dempsey
Key player
With eight goals during the qualifying campaign, and 36 in 101 caps, captain Clint Dempsey continues to provide the attacking thrust he demonstrated so regularly in the Premier League with Fulham and Tottenham. The 30-year-old is now at Seattle Sounders.
An honourable mention, too, for forward Jozy Altidore, who excelled during the final qualifying group phase.
The boss
Former Germany player and head coach Klinsmann has been questioned in the US media for his constant tinkering with formations and personnel since he took charge in July 2011.
But Klinsmann, who has lived in California with his American wife for 15 years, has created an atmosphere of confidence and competition.
How they qualified
They recovered from an opening 2-1 defeat by Honduras to finish four points clear at the top of the six-team final group phase, winning all five home matches.
World Cup record
The USA will be playing in their 10th World Cup, and seventh in succession.
They were third in 1930 and quarter-finalists in 2002, losing 1-0 to Germany.
Fifa ranking: 14