cloud computing as a global IT Platform for doing business internationally

what is cloud computing?
what does cloud computing means for a business?
expansion of the global market?
areas where market has been saturated?
places where new oportunities exist?
issues with infrastructure (power, technology, logistics)
example of cloud computing (google, hotmail, amazon)
challenges (political, economic, technological)
cloud computing in information systems used in innovative and useful ways
implications (security, government, liability)