For those of you that speak Japanese there is a new Olympus patent No. 2013-187811 describing how the sensor shift tech works (Source: http://astamuse.com/ja/published/JP/No/2013187811).
The patent shows how the shifting creates high-definition images with 1/2 pixel shift and 4 frames.
The E-M5markII will actually increase that to 8 frames (and 40MP resolution images). The sensor used will be the same as the one of the current E-M5 (16MP and no phase detection pixels). But the processor will be new and manage to create those 40MP images on the fly!