My car is in the shop now for the 5th time (in less than 5K miles) with this problem. They have replaced the IAC (idle air control) twice and reprogrammed the computer once. The IAC replacements seemed to work for a little while. Who knows what they will do this time.
The dealer says Ford has no bulletins out about this. I'm wondering if we shouldn't write a group letter to Ford/SVT describing our individual experiences with "RPM hang".
If anyone is interested in sharing, email me your story (pinkrton@mcw.edu). I'll combine them and send them to Ford. Can't hurt, I suppose.