I would be surprised if Android O launched before the Pixel 2 releases. But I will watch out for it in the Moto Z2 Force if you are right.
Meanwhile, to me the important thing is that as Android O official release is now really close, we can expect official details to be released soon on the Pixel 2. I saw Tech Radar saying that the 2 will likely be the first to carry the Snapdragon 836 processor from Qualcomm, indicating at least a 10% performance improvement. Add to this the squeezable frame, possible awesome colours (again Tech Radar rumours from recent renders), better camera, etc, and the 2 is setting up to be a really great phone.