Yep - he loves it. He has been an Aperture user for a long long long time - almost as long as me. He feels about Aperture 3 the way he felt about the D3. You can read his notes here. He was a beta user and has been using it for months. You will have to wait another day on my first impressions. So take a gander at his not so first impressions.
Ps. There are a couple of bugs - nothing earth shattering yet but a stumble here and there. Subtle, these will get fixed quick in all likelihood.