A German site, Digital Kamera, has published a new review on the Panasonic . As with other reviews, they have also pointed out that when wide open, the corner resolutions could be better. But other than that, this lens is a strong performer. They did mention that the Olympus f2.0 lens offers higher resolution, especially at the edges, presumably at f2.0.
Oh and the site noted that the final version of the lens will NOT have that purple hue that has been present in the early/beta copies that have been used by various reviewers (see the picture above). Pity, as I actually thought that purple hue was rather cool.