Olympus has been mysterious about this sensor: its size and pixel count specs roughly match the GX1 and G3, though not exactly, and Olympus says that it is different (but how different?) from any previous sensor, and has given it ISO speed settings up to 25,000, one stop more than previous sensors.
But none of that really matters; let us see how it performs. The high ISO speed JPEG samples clearly control noise with some smoothing, trading away some resolution, but that makes sense to me, and seems to give usable web-posting snap-shot grade images all the way to the top. (If you instead want sharper, noisier low light images, shoot raw!)
Anyway, rather than going blind comparing 100% crops on screen, I am looking forward to testing its promises about AF speed including improved handling of moving subjects (C-AF) through a new 240fps sensor read out for AF, and also seeing if I am comfortable with the performance of the tiltable LCD and non-tiltable EVF.