I have the Panasonic system with both an GF1 and a GH1 and five lenses. I can get all of that, plus a charger, several batteries and a Mac Air, into a bag smaller than the average briefcase. The problem (as I see it) with the Sony system is it gives up a little bit of smallness (in their lenses -- the size difference of the bodies isn't significant) to get a little more image quality. But if I want more image quality than you get with m4/3, I'd want significantly more -- I'd go to my Nikon FF and accept the size penalty. The basic thought of M4/3 isn't ultimate image quality, it's size, with quality good enough for most publication, and that's what you get. I agree, if you're a guy who walks around with one camera body with a pancake lens, then the Sony is as good as the M4/3. If you have to run some place with a *system,* it isn't, because it's bigger and heavier. I actually think Sony would have been better off joining the consortium, and making a m4/3, than going off with a unique and brand-new mounting system. One thing I'm curious about: will their lenses cover FF? That would be an interesting possibility -- eventual FF bodies -- but I suspect the lenses are made specifically for the sensor size, like Nikon's DX lenses, and won't cover full frame. Two other notes: a big deal is being made about the slight size difference in the bodies...but Sony has only an exterior flash. It's supplied with the body, but if you put it on, the Sony is as big or bigger than the Panasonic. Sony also (according to DP Review) cut down the tripod mount until it is inadequate; and even if they hadn't, I wouldn't have had a lot of confidence mounting one of those big honking zooms on that tiny body, on a tripod. That can be fixed in the next iteration, at the price of getting larger.