No, the use of private VPNs make it very secure. Need to have a decent ISP though, especially for your VOIP conference calls.
With the advent of telecommuting, many employees have "grown into" their jobs and locations so that if the spigot is turned off, as is happening at IBM, HP, Honeywell, etc... they will find themselves needing to do a long commute to an office where there are none of their co-workers. So, the theoretical advantage of face-to-face team work is lost, because the actual coworkers are in another city or country.
I know one person in this situation that does con-calls most of the time to the detriment of the native workers in his cubical neighborhood. Imagine you are a quiet in-office type, and some foreigner employee is given an office next to you constantly and loudly on the phone.
I’ve done telecommuting (although I used my own speakerphone for the phone calls.) But you have to require folks to use the company’s equipment for access instead of their own. Otherwise it becomes a nightmare during discovery for litigation. And you still have the problem of inadequately secured hardware, worker’s comp issues, and man in the middle issues.