The article title doesn't specify which cup we're talking about. World Cup? European Championships? FA Cup? Given the ambiguity, it's perhaps interesting to look at this from the angle of someone who likes to have a little flutter when a major football (soccer) competition is taking place.
As you'd expect, the strikers from the sides that are considered pre-tournament favourites will typically be favourites to end up as top goalscorer and will have the lowest odds. Therefore, one way to decide on who you are going to pick is to go with one of these players. In a World Cup, for example, players from Brazil, Argentina, Germany and Italy will usually feature near the top of the goalscoring charts.
Another option is to wait until the initial groups are decided and then look to see which good quality teams have found themselves placed in a weak group. In the 2002 World Cup, Saudi Arabia were embarrassingly poor and Germany 8-0 and their striker Klose helped himself to a hat-trick. He ended up with 5 goals and finished second top scorer. Similarly, in the 1994 World Cup, Russian striker Oleg Salenko scored 5 goals against a shambolic Cameroon team and this helped him become a surprise joint top scorer in the competition with 6 goals overall.
Another option is to look for teams who build their play around servicing one key player. In years gone by Bulgaria didn't tend to score that many goals but everything went through talisman striker Stoichkov and this helped him share top scorer spot with Salenko in 1994.
Finally, let's consider briefly the 2010 World Cup finals. We don't know all the teams that will qualify yet and we don't know who they will be placed against. However, we might expect the likes of Torres (Spain), Robinho (Brazil), Aguero (Argentina) and Podolski (Germany) to be amongst the main contenders. With it being the first World Cup to be held in Africa, however, it will be interesting to see if any African strikers can gatecrash the party. Hosts, South Africa, will be looking to Blackburn Rovers striker Benni McCarthy, and (if they qualify) Ivory Coast will have Chelsea's Didier Drogba, Cameroon will have Barcelona's Samuel Eto'o and Egypt will have Wigan Athletic's Amr Zaki.
For what it's worth, my money would be on Robinho for top scorer but I think Drogba could be quite an interesting each-way bet. I'm sure there will also be quite a few bets on players who aren't strictly speaking strikers. Portugal's Ronaldo scores goals for fun for Man Utd, whilst Argentina's Messi and Brazil's Kaka also weigh in with their fair share of goals. However, despite the fact that they are big names and great players, past history tends to suggest that it will be centre forwards who will end up topping the goalscoring charts. Now wouldn't it be nice if I could predict the next Salenko-type shock top scorer?!