Noise?
I must have got very lucky in my GT. The only noise comes from the exhuast, and then only when I gas it. It just sounds sweet! No rattles, no squeaks, no wind noise. But I did have the same vibration at 65-70 as was mentioned.
I took my 07 GT to my dealer, and made the Shop Forman drive the car with me beside him. I never rode in the right seat before, or since but you cant see the speedo and tach numbers from over there. But when he was driving, I felt the vibes, and told him "were doing 70 mph right"? He nodded, and said he felt it too.
When we got back, he checked with Ford, and there was no TSB but some other kind of mention of this problem. Enough to warrant a new super balanced "supposedly" drive shaft. It only took three days for the shaft to arrive, and 15 minutes to have them install it. I say, go for a new shaft its free for the asking.