Brian Parsons

Discussions about cloud computing security often fail to distinguish general issues from cloud-specific issues.

Here is a great overview from Security & Privacy IEEE magazine of common IT vulnerabilities and how they are impacted by the new cloud paradigm.

The article starts off defining vulnerability in general and then goes on to establish the vulnerabilities that are inherent in cloud computing models.

It really boils down to access:

Of all these IAAA vulnerabilities, in the experi­ence of cloud service providers, currently, authentica­tion issues are the primary vulnerability that puts user data in cloud services at risk

...which  is really no different than anything in traditional IT.

via InfoQ: Understanding Cloud Computing Vulnerabilities.