At the moment I'm shooting mostly with the X100 and GRD3, but I'm watching developments in m43 and Nex with a LOT of interest. I have a Nex and a GH2 and will likely go mostly one way or the other depending on how quickly and well m43 comes out with the camera that wins me back with the extensive collection of lenses I already have vs how quickly and well Sony comes out with a slightly better camera and a few much better lenses. If the Nex 7 and the Zeiss 24mm arrive reasonably soon and live up to expectations, I could go hard to Nex and the m43 would just stay on hand for telephoto and ultra wide angle work, which I don't do a lot of. If, OTOH, the AF and flip screen on the new EPL3 live up to my hopes and the IQ doesn't suck (doesn't have to be quite as good as the GH2 or G3, but I'm hoping for better low light performance than the EP2 or GF1 had), I'll likely jump back into m43 and sell the Nex. But seriously, I like the X100 and GRD3 so damn much I'll probably keep using them for 90% of what I do.
-Ray