Some initial thoughts (feel free to agree/disagree):
1) Small footprint, that is even with a built in EVF
2) Compatibility with existing Nikon lenses (although handling will be disproportionate)
3) Multi-function accessory port (the accessory combinations are pretty interesting) - although can't fit existing Speedlights?
4) Performance on paper looks good (et al AF speed, 1080 video shooting modes, etc)
Cons
1) No manual shooting modes (APSM) modes, seems like a souped up PnS
2) Button layout a little too minimalistic for my liking, would prefer more buttons for easy accessibility
3) Seems pricey in relation to competing alternatives
Might still go with m4/3 after all...