Possibly. That adds a fair bit of friction though. My workflow right now is to use Org to organize projects, do time tracking, and keep relatively free-form notes on each task I work on. Currently stored in Dropbox so that the same set of files is auto-synced to multiple machines.
Forgetting to commit and push my notes before switching from my Mac laptop to my Linux laptop would be pretty disappointing, compared to them magically showing up. On the other hand, if I had multiple people working on the same set of org files in Dropbox, I suspect Dropbox would start having trouble with conflicts pretty quickly.
And... unfortunately... it seems unlikely that someone I'm going to hire is going to be on-board with project management in Emacs. While I'd love to have an army of Emacs lovers working for me, that seems unrealistic to expect :)
Could collaboration be done using a public git repository?