Peter, Jono and others,
One of the most surprising things with the E-5 is what happens when a low-ISO file is enlarged. If I re-size it to the same height as a photo from the A850 or 900, the amount of detail seems to be the same as with the Sony. Noise increases, but my guess is that it can be controlled rather easily with some noise detergent, at least up to a point. DR of the Sony seems better, which is to be expected.
Like Peter, I prefer the colours from Olympus, but I like Sony better than Nikon in this respect. Difficult to discuss taste.
I went out to try the A850 today for the umpteenth time. It's nice, but I like the ergonomics of the E-5 better. The good lenses for the Sony are good, but they are all expensive and they are all rather large. How solid everything is, I don't know. It's an industrial product marketed through chain-stores, which brings me to another side of this:
When Sony launched their Alpha-series, they were everywhere in Bangkok. Almost all of the good camera shops had a more or less complete selection, and they promoted it actively. Now, they are mostly to be found at Sony's own stores and some chain-stores, except the odd camera that can be found here and there. This of course doesn't say much about the quality of cameras and lenses, but it says rather a lot about what kind of after sales support that can be expected. The staff at the chain stores can usually list a number of key features for each camera, but try to explain a focusing problem. "Yes, but it has 24 megapixels."
And as much as the (very good) Sony cameras and lenses give me the feeling of mass-produced commercial goods, the E-5 and gives me the opposite feeling: It doesn't look very fancy, but I get the feeling of holding something that somebody crafted from one solid block of aluminium, especially for me. The 14-35mm gives me that feeling to an even stronger degree.
This will obviously not do anything whatsoever for my photography, but as a tool, the Olympus suits me for some reason. Maybe it's just nostalgia (my OM-1 was my main camera for 30 years) and maybe it's because I see some fantastic photos sometimes, particularly from the 14-35 and 150mm lenses.
Nothing decided yet, but...