The simple fact that - in low light - Canon G1X looses to Panasonic GX1 in spite of relying on a considerably larger sensor is a clear indicator that Canon has created a brand-new camera sporting an "old" sensor.
The comparison with a last-generation m4/3 sensor will be even more humiliating for Canon when DXO Mark will have Olympus M5D test available.
Very stupid of Canon, I think: with G1X they have shown they can produce a very large-sensor compact equipped with a good, small zoom-lens. If G1X sensor (and data processing power) were "top notch", all m4/3 EVILS would be easily beaten on all terrains, except flexibility (lens interchangeability). And most users would go for G1X because most don't need interchangeable lenses when they have a nice zoom-lens. As things are, though, I would rather go for a last-generation EVF-equipped m4/3 EVIL camera: either Panasonic G3 or - with a larger budget - Olympus M5D.