In reply to JDal:
> I have the same feeling about my Sony sensored E-M5. And I don't have a problem with the noise, this "4/3 so it's too noisy" is way overstated. More to do with early Panny sensors I think. It's the small body/lens combo's I really like over the APS-C offerings.
>
> This shot of a church concert sums it up in a way, there was no photography during the performance. I used the TINY 45mm f1.8 on my E_M5, everything set to silent and no AF assist light. Camera sat on knee with LCD flipped out, ISO 3200/f1.8, rubbish ambient light, unassisted AF was really fast and accurate.
http://farm9.staticflickr.com/8059/8198886943_caffa2cd13_o.jpg
It's a good shot, but the Panasonic I mentioned as being too noisy has a sensor much smaller than four thirds (1/2.3"). The problem I have with noise is that the photo looks OK until you crop it, and then you start to get an irritating fuzziness creeping in. That really interferes with some shots, particularly a landscape.
It's a bit like when people used to argue that you don't need more pixels on a sensor, because (say) 10MP is enough to print out to A3 size (or whatever the guideline is). Yes, but if you crop out half of the shot you only have 5MP and the resolution is noticeably weak at that level. Nikons' D3200 has 24MP: which sounds like overkill. But from this you can crop by 50% and still have 12MP resolution. That's like having an extra 100% telephoto zoom available on a 12MP camera, whilst at the same time having the wider angle available for improvements to the composition.