RJpieces does have a point...
Cities like Sydney, Melbourne, Aukland, Seattle, Vancouver, Florence, Zurich, Munich, Hamburg, even San Francisco, Amsterdam, Barcelona, Chicago, Houston, Copenhagen, Oslo, Vienna are simply way, way too small to even be considered 'world-class' cities. Many of these cities do NOT have metropolitan populations exceeding 5 million inhabitants.
Mind you, all of these cities are absolutely beautiful (except for Houston!), have very, very high living standards and very developed cultural and civil institutions. In additiona, the quality of life in many these cities is substantially superior to that of 'world class' cities; their size, however, is a lacking...
Obviously, the criteria used to classify a 'world class' city is highly subjective, but should include:
- Large metropolitan population; over 5 million inhabitants
- Large commercial sector, with direct ties to global enterprise, home to large, multi-national, financial, media, legal and commercial institutions
- Active cultural and civil institutions, with a dynamic press and significant artistic and cultural talent
However, I would expand the list:
New York, Los Angeles, Mexico City, Sao Paulo, Buenos Aires, Toronto (too small?)
London, Paris, Berlin (a bit small), Madrid and Rome (they're also a bit small)
M.E. and Central Asia and Africa
Frankly, there aren't any 'world-class' cities in either Africa or the M.E./Central Asia, despite an abundance of huge metropolises, such as Lagos, Cairo and Tehran
Tokyo, Seoul, Taipei, Hong Kong, Singapore, Beijing, Singapore, Mumbai (not really a 'world class' city, but perhaps could be in a few decades)