I really take offense to cars noises: windw noise, rattles, squeaks, etc. But I haven't noticed anything abnormal with our 07 Limited. It is super quiet, even at high speeds. Occassionally, if there is cross wind on the highway, I notice some wind across the driver's side mirror, but only because everything else is so darn quiet.

I had a bad windshield seal once on our 2000 Expy. Might be worth checking. Can you locate the area your noise is coming from?