From a business point of view I question whether or not the cloud and all its attributes are in fact good for business. For example, and this is not an negative attribution against any company I may mention, SaleForce.Com has sold many CRM applications to small businesses. When I was doing technical sales supporting Microsoft CRM I sold Microsoft based on the fact that unbeknownst to most sales people, SalesForce.Com owns the business' data. They have the encryption key; they have the backups. That is a security issue for any organization. Banks, Credit Unions and Insurance companies cannot afford to put their data at risk with a third party.

Third party email systems hold the same risk. All are vulnerable to hacker attacks and the like.

So much for my two cents