I have about 7000 miles on mine and it has had the first oil change. Sometimes I notice it more other times I do not. It may just be me. That said, I am sure there are differences between each car.

Unless it is very violent, I would assume it is normal. Maybe try another 07. I have an 07 so I cannot speak for the 08s.

That said, I have asked people (riding) if they can feel it. They say they cannot or they at least don't notice it. Did you and your wife feel it while riding or just while each of you were driving it? You will certainly feel it while driving it.

Mike