We made the connection! Our flight landed from Spain at 9:25, but by the time we were at the gate and had managed to get off the plane (we were seated at the back of the plane) it was 9:40. I must say I never even saw any buses linking terminals...you can do it all on foot and it is well marked. There are horizontal people-mover-conveyor-belt things linking the terminals in sections, but of course when we were in a hurry on the way back to the USA almost none of them were working. We arrived in 2D and our gate leaving was 76E. 76? 76! I literally felt like we ran for 2 miles, I would love to know the actual distance.
So we were off the plane at 9:40 and did pretty much a dead run and got to the gate at 10:00. You end up going through security multiple times. I got patted down twice (probably because I looked like I was insane) and I ended up telling my youngest son just to leave his shoes OFF and run! (they were hiking boots that required a lot of tying and untying). The flight left at 10:20 so at 10:00 they could have given our seats away. In fact, as they scanned our boarding passes at the gate they all came up "Invalid Ticket" on the computer because we were "late". No problem though. It took us probably 10 minutes to go through the official stuff at the gate, scanning boarding passes and getting our carryon bags searched and patted down yet AGAIN!
What helped us was that it was in the morning on a Friday in February, so traffic at the airport was light. Security lines were blessedly short. AND there was a group of 70 people connecting from a Rome flight that was also really short and they were tearing along about 50 yards behind us to make the same flight (it must have been quite a sight, all these Detroiters running through the Paris airport). Also, no one was waiting to fly standby and while the flight was full, it wasn't overbooked, so they weren't giving our tickets away right at 20 minutes before the flight. Our flight ended up taking off almost 35 minutes late because of all the people with short connection times, but they made up the time in-route and we landed in Detroit on time and everyone's luggage made it!
I think we would have had a very different outcome if it had been on a busy day/time at the airport, if the flight had been overbooked, or if it had been in the high travel time.