Enterprise-wide GTDNext for a small start-up

Hidey ho,
I am new to GTD and GTDNext and already finding it very useful.
I am part of a small startup company with 3 local employees and 6 at other locations.
Can GTDNext be implemented as an enterprise-wide tool to track projects and everything involved in a new venture?
Any tips on how to do that?
One set of log-in credentials that we give to the three local employees?
Thank you,