Photozone.de posted their review of the brand new Canon EF 100-400mm f/4.5-5.6L IS II lens. And it is a very positive one.
From the conclusion:
The king is dead, long live the king! Seems as if Canon wanted to show the new mirrorless kids who is still the boss around. The Canon EF 100-400mm f/4.5-5.6 USM L IS was already good but the Canon EF 100-400mm f/4.5-5.6 USM L IS II is even better. Canon managed to improve the image sharpness substantially (mostly in the lower range). The image center is now dead sharp and the borders and corners are easily very good at mainstream settings. The very low amount of CAs (at and beyond 200mm) is highly impressive. The vignetting remains rather typical for a lens in this class, so you will be able to spot some light falloff at fully open aperture (300/400mm). Image distortions are well controlled. The quality of the bokeh is good although the best prime lenses continue to have an edge here. Bokeh fringing is not an issue due to the relatively small max. aperture.
- EF Mount L-Series Lens/Full-Frame Format
- One Fluorite and One Super UD Element
- Air Sphere and Fluorine Lens Coatings
- Ring-Type USM AF Motor, Internal Focus
- Optical Image Stabilizer with 3 Modes
- Rotating Zoom Ring & Torque Adjustment
- Weather-Sealed Design
- Detachable, Rotatable Tripod Collar
- Rounded 9-Blade Diaphragm