Check the gallery here: http://www.pbase.com/nickdemarco/zeiss_25
I also did a 25mm lens test with the Zeiss and the Canon 16-35mm f2.8L II and the Canon 24-105mm f4L. The results (the Zeiss wipes the floor with the other two) are in the first sub-gallery.
First impresssions:
As the reviews said, incredibly sharp. Nice cool Zeiss look. Good bokeh wide open. Macro ability is crazy, you can focus within 2 inches of the subject.
It's a quite heavy lens (nearly .5 kg) and much bigger than my Contax 18mm f4, but still smaller than the Canon 16-35mm f2.8L Mk II. Being only in Nikon fit it took a while to get used to everything be the wrong way around, especially as 90% of the focus ring is for 6 foot or under.
The lens and hood are certainly very solid and well made as you would expect. I'm pleased to discover it has a 58mm filter thread as I had just bought a 58 infra red filter - you can see the experiments I have done with IR in the gallery.
I had a trip to Paris last weekend and had expected the 25 to come with me, but it had not arrived. Instead I used the Contax 18mm f4 a lot for wide stuff. The 18 excelled itself in the bright sun of Paris, especially for architecture. I am pretty sure though that the 25 is sharper, much sharper. Generally, the 25 is a more useful range for me. But I ill be hanging on to the nice quite smll 18 for those extra wides.
I have gone through a few wides, but think the Contax 18 and the Zeiss 25 will now be all I really use, so will probably be selling a Leica 21, Olympus 21, Leica and Olympus 28 soon (I shall keep my 16-35L for those rare times I need AF).
The 25 will from now on be my first choice for wideangle photography of wider than 35mm.