Are the days of English as world language counted?

[Skybird]

http://www.economist.com/node/17730434

English is expanding as a lingua-franca but not as a mother tongue. More than 1 billion people speak English worldwide but only about 330m of them as a first language, and this population is not spreading. The future of English is in the hands of countries outside the core Anglophone group. Will they always learn English?

Mr Ostler suggests that two new factors—modern nationalism and technology—will check the spread of English.
(...)
English will fade as a lingua-franca, Mr Ostler argues, but not because some other language will take its place. No pretender is pan-regional enough, and only Africa’s linguistic situation may be sufficiently fluid to have its future choices influenced by outsiders. Rather, English will have no successor because none will be needed. Technology, Mr Ostler believes, will fill the need.