Dpreview (click here) tested the Sony NEX cameras
1) The NEX images do have slightly less noise than the smaller sensored Olympus E-PL1 but the images do not have much more detail
2) Olympus jpeg engine works better than the Sony engine
3) Very bad handling of the NEX
Overall score:
Nex5 64%
E-PL1 69%
Read the review at: Dpreview