Hi Mike ..... I haven't gone down the M43 route but this is the first camera to tempt me. I realise after a fruitless affair with an Panasonic LX5 that however able I cant cope without a viewfinder ... and if I have to use a viewfinder then an articulting LCD is vital ... The Olympus looks quite good ... and to be honest a bit weird .... and looks like good High ISO performance, good viewfinder and screen BUT ...... are you sure . I have just upgraded from my lovely clunky old K200D to the K5 .. and I cant believe it!! It is small neat and .... and this is the point ... with a fabulous handgrip ... just for me the best ever .. it almost feels like part of me .... and I just wonder how the OMD will feel in the hand ..... Not a reason to avoid ... but I wonder if in a year or two which of these lovely cameras you are using ..... I think the K5 is just fantastic ..... hope you find the OMD even better .. but somehow I doubt it ..... and you'll miss that 35 Macro ...