One of the complaints often levelled at Apple's and Mac OS X is that they cannot be used for a variety of business.
Some of this is historical - for years Apple's were seen as the only choice for publishing and graphic design. Unfortunately they were accused of only being capable of doing these tasks.
As a user of Macs for the last 16 years, I can tell you that there are few things they are not capable of. I was IT administrator for an advertising agency and for years we survived without ever needing Windows. We handled all our communication, email, accounts and project management.
How Apple has developed a website designed to highlight exactly what Mac OS X is capable of, and where it is and can be used. Called Mac at Work it contains examples, online seminars and information on applications and environments where Macs can be just as capable a solution as any other alternative.