Originally posted by deadwolfbones Dunno, seems accurate to me.
I've used top end gear with both APS and 4/3rds (K20D, DA 35mm Ltd, DA* 16-50 & DA* 50-135 and the E-3 with ZD 12-60 and ZD 50-200) and in every case but the DA Ltd, the IQ from the 4/3rds gear was either very similar or better. Especially in terms of corner-corner sharpness, fall-off and CA control. Definitely not noticeably worse, even in terms of high-ISO...
That's not to mention the very real advantage that the crop factor provides for tele-photo photography, allowing amazingly fast and relatively compact lenses like the 150/f2, 90-250/f2.8 and 300/f2.8 (300mm f2, 180-500mm f2.8 and 600mm f2.8 equivalent). Anyone who's seen a Zuiko 300/f2.8 lined up next to a Nikkor 600/f4 will know exactly what I mean...
I'm not saying that there aren't strengths and weaknesses inherent in both systems, but to say there's 'no advantage whatsoever' is just uninformed...