With Spain in crisis and Turkey very unstable and compromised recently, Tokyo seemed the only sensible selection for the IOC. Thus today's announcement comes as no surprise.
Today in Buenos Aires 104 members of the IOC voted over the hosting of 2020 Olympics. First phase saw one bid of the three finalists eliminated and that third bid was Madrid, for whom this was the 4th attempt. Fourth and perhaps the weakest ever as the country is economically unstable.
The final vote came down to Istanbul and Tokyo of which the first city was bidding fifth time already, but just like Madrid saw its bid compromised by recent events: corruption in professional sports, human rights crisis and the war in Syria not too far away. Thus the selection of Tokyo is no surprise.
In 2020 the Japanese capital is to have a brand new National Stadium replacing the old one that held Japan's first Olympics in 1964. The new 80,000-seater was designed by Zaha Hadid and has a unique outer form.