I have almost 5K on my 05. It does behave different now than when i first got it but I have to be skeptical and think its due to the weather. The 60-70 degree mornings and evenings here in FL is awesome. The car runs like a raped ape during those times. The big test will be when we have the 90+ degree weather if it still runs the same in the middle of the day.
There was a post a while back that said that our computers adapt to how we drive and I agree with that statement. If you drive your car like an old lady (no disrespect) for a while and then try to romp on it--it feels sluggish/slower (at least thats how if felt to me) so from that moment on I make sure that I DRIVE my car.