This is normal, it doesnt have to shift down. The turbos spool up and provide all the power you need to overtake. Unless you need to gun it you should be fine with what I call the "suck n go."
I disagree - this is not normal. I currently experience exactly was Ravensfan79 does. Very poor performance in any gear at or below 1500 rpm's. When you finally push the pedal half way down, the transmission finally downshifts and the power really kicks in - a very dangerous situation with the delay, unknown response time, and a sudden burst of power. Did not do this when I bought the car, but within a few months I experienced this. About nine months later I had the transmission memory reset when a tech agreed there was a hesitation issue. No change within the first week, but then the car operated perfectly for a couple of months, then back to the same problem. Amazing night and day difference! Ford states this condition is normal - to save fuel. But this does not explain why it has operated perfectly for months. If it drove like this on the test drive, I would not have purchased the car .... tough to watch Honda Civics accelerate faster than you without pushing the pedal to the floor! I test drove another SHO on the dealers lot and it was also fine.