Photo.net has published a first impression review on the Olympus. The reviewer thinks thatcan replace other APS-C class DSLR cameras, though, not quite up to the full-frame DSLR quality.
Their overall impression: My overall initial impressions are very positive. I really enjoy using this camera. It is the first mirrorless camera that has made me say “Hmmm, do I really need my APS-C DSLR any more?”. No, it’s not going to make me personally get rid of my full frame DSLR and bag of high end f/2.8 zoom lenses. But it sure could become my “family/friends/travel/serious-photography-where-I-don’t-want-to-haul-a-huge-kit-around-but-still-need-a-good-camera” camera, and for me, that’s saying something. Every other mirrorless camera that I have liked so far has been a “I’ll add it to the bag because it will be useful for ________ situation”. However, none had yet been able to threaten to become a “replacement” for existing gear. Thehas a chance to be the kind of camera that replaces gear I currently use, and I think that’s kind of a big deal.