The final verdict won't come until September 2013, which means 17 months of aggressive courtship and IOC chin-stroking.
To prep you for the long road ahead, I've laid out the proposals as I see them—strengths, weaknesses and potential bugaboos.
The case for Tokyo is twofold.
1. Tokyo needs the Games to stimulate an economic recovery.
2. Tokyo needs the Games in order to overcome the psychological wounds of the 2011 tsunami disaster and demonstrate its resilience to the world.
The balance between pragmatic benefit and symbolic significance seems to have gained some traction, with multiple reports saying IOC decision-makers were quite taken with the Tokyo proposal.
From the AP (via ESPN):
Tokyo, which hosted the 1964 Olympics, received the highest praise in the IOC report, which said the Japanese bid presents "a very strong application."
But the argument against Tokyo is also double-pronged.
Perhaps the most significant hurdle is that Tokyo hosted the Games back in 1964.
The objection here is pretty basic: been there, done that.
The second and somewhat related argument against Tokyo is that the host nation isn't all that excited about the bid.
The previous bid for Tokyo to host the 2016 Olympics was not exactly greeted with open arms by the public. Only 55.5%, the lowest level among other candidate cities, supported Tokyo’s bid according to an International Olympic Committee poll.
So far opinion polls have also been more favorable than last time, though still lower than the other bidding cities. A nationwide poll taken in January showed that 65.7% of respondents in Tokyo supported the city’s hosting of the 2020 Olympics.
The combination of these two elements paints Tokyo as a safe but uninspired choice, backed by a populace that would need serious stoking before it would fully embrace another Olympic Games.
Spain's economy is in a mighty tailspin, and Madrid's contingent sees the Olympics as a potential stimulus.
That argument, however, rubs two ways.
If Madrid wins the bid, and its economy improves as a result, the IOC looks good by association and presumably has more leverage in future host city deliberations.
What's more, the desperate need for economic resuscitation seems to have helped rally public support regarding an Olympic push.
On the rusty side of that coin, the IOC has to gauge whether Spain's economy is strong enough to support a modern Olympics (with all the varnish fans have come to expect).
"There was a warning, however, as the IOC pointed out 'careful attention would need to be paid to Spain's economic outlook.'"
Turkey is the only country of the three remaining to have never hosted an Olympic Games.
In that regard, Istanbul fits the Beijing 2008/Rio 2016 prototype: new city, new country, new culture, underlying narratives about modernization and global emergence.
But Istanbul has a monster obstacle in its path: Turkey's active bid to host the UEFA European Football Championship that same summer.
The IOC won't allow the country to host both events, meaning Turkey and Istanbul will have to jointly appoint a priority and risk coming up empty.
The Olympics are more popular worldwide, but in soccer-crazed Turkey, the debate will run hot.
For a country that has won just 82 Olympic medals across six disciplines, the Games aren't necessarily front-page material.