I haven't gotten to use the Nex as much as I would have liked to in the last couple of weeks, work, grass cutting ect. But my first impressions are pretty good. First the tilting screen is sweet. Navigation another thing. It is hard to navigate if you are use to a DSLR. There is no quick way to change ISO or much else. The best way I have found to shoot is aperture priority or shutter priority.
Focus speed is, well, fast. I use the 16mm and it is as fast as some DSLRs I have owned. Manual focus is also very good. When you focus the screen enlarges your subect and it's easy to get focus. I haven't used the screen in bright light yet.
Noise is also very low. Clean ISOs up tp 1600 and 3200 ISO, personally I wouldn't go any higher as noise becomes noticable.
When the camera first came out many were calling it ugly.lol But from the get go I was impressed with the grip. It feels very good in my hand and is easy to hold and shoot. I haven't tried IS out yet either. I keep forgeting how to navigate to turn it on.lol
Start up time is a bit to slow too. I also wish I could use a remote shutter release since i shoot at night a lot but have yet to find a remote timer. The Nex 5 can be fired with a wieless remote.
Is it better than Olympus? Well the IQ is. It is right up there with my E5. If the lens was a little sharper it might be equal or even have an edge. But I have to remember I am using the kit lens on the Nex, Soon I am going to try my Leica and Voigtlander lenses on it.
I wouldn't say over all it is better than Olympus, just different. With Olympus you can use a EVF or OVF, a plus. Olympus also has an edge on lenses. They have more choices there.
All in all I have liked all of the EVIL cameras I have used but no one has hit a homerun with me yet. As good as they are my problem isn't IQ but function. So far I think the Fuji X 100 appeals to me the most but you can't change lenses and the price is out of my league for what I would use it for. If I am going to lay down that kind of cash I want a weather sealed DSLR. Not a P&S.
Sooner or later some one is going to hit it out of the park. A camera that is easy to shoot in manual and has a EVF and $800.00 or less.
I think Canon and Nikon both are watching the market and may have a few surprises in mind.
Oh if I could only just slide a sensor inside my M3.