How to measure cooperation between different offices?

Hi guys, 

I'm a new listener to the career and manager tools podcast, and in all honesty this far it's been a blast. before I started listening to the podcasts I felt trapped in my current position and considered quitting, even if it meant a step down in pay.
 
However, having listened to your them have given me both a new understanding on how to change things at our company as well as giving me a hope for the future.
 
Now on to my question, I want to measure how well a project that I'm pushing are going. We are a very international company in that we have five or six offices all developing their own product lines and I'm running a project to increase cooperation between us. Now, I have a couple of ideas on how to measure this (number of features that incorporate more than one product line for example), the problem is that they don't seem to actually measure the right thing... Anyone of you have any suggestions? 
 
Regards, 
Tony