Healthcare IP Partners deploys security measures on all its computers in case they're lost or stolen. With Macs and iPhones (Healthcare IP Partners also issues iPhones), the odds of a theft increase. Kelly says he makes sure new Mac users are aware of this heightened risk.

It's not just lip service, either. San Francisco police, for instance, this week about a rash of daytime iPhone robberies. In one case, three teens saw a man talking on his iPhone, held him up at gunpoint and stole his phone.

A CIO of a Silicon Valley law firm, speaking on condition of anonymity, told CIO.com that some Windows apps run faster over a virtual machine on a Mac than on a PC. On the other hand, says Kelly, some Windows apps with Mac versions don't run well on a Mac.