Cloud Computing has attracted a lot of attention in recent times. The media as well as analysts are generally very positive about the opportunities Cloud Computing is offering. In May 2008, Merrill Lynch (2008) estimated the cost advantages of Cloud Computing to be three to five times for business applications and more than five times for consumer applications. According to a Gartner press release from June 2008, Cloud Computing will be “no less influential than e-business” (Gartner 2008a). The positive attitude towards the importance and influence of Cloud Computing resulted in optimistic Cloud-related market forecasts. In October 2008, IDC (2008b) forecasted an almost threefold growth of spending on Cloud services until 2012, reaching $42 billion. Same analyst firm reported that the cost advantage associated with the Cloud model becomes even more attractive in the economic downturn (IDC 2008b). Positive market prospects are also driven by the expectation that Cloud Computing might become the fundamental approach towards Green IT.