Hmm... I've just been thinking about what I would design if I had an unlimited budget and a suite of engineers to build it for me...
It would look like a Leica MP, be that size, and that heavy (it would also be splash/rainproof).
Have a zooming optical viewfinder (like the Contax G), with an EVF overlay (like the x100)
Natively accept m-mount lenses, and take advantage of their rangefinder coupling (somehow... probably electronically, I'm not fussed about an actual rangefinder, so long as the use and function is the same)
Support a small line of exellent autofocus lenses (these lenses would resemble the new Oly 12/2... but cover a full frame. I don't mind waiting for these to appear one by one).
Have a hotshoe, a shutterspeed dial, an ISO dial, and a locking on/off switch, and an on-top lcd a-la M8.
Use an oversized Full Frame Sensor, so that no matter what format (1:1, 4:3, 6:4, 19:9) you shoot in, the diagonal is always the same as the image circle diameter. (a bit like the GH line, only done properly; perhaps using a hexagonal sensor in a nod towards manufacturing efficiency.) This sensor should allow live view, be critically good to ISO3200, and be generally exccellent - ooh, maybe it should be removable/upgradable (like a CPU on a motherboard? Only alignment would be a bit more exacting)
And until this appears, I'm not buying a new camera again!!!
I don't dream of cameras. I have good ones. If I could design my dream camera from the ground up, it would have the flip screen of the Nex, the silent shutter and low light IQ and hybrid viewfinder of the X100, the snap-focus tool of the GRD3, the INCREDIBLE reflexes of the EP3, and m43 sized interchangeable lenses. I'd also love the incredible DOF of the GRD3, but I think that and the IQ of the X100 are mutually exclusive given the sensor sizes involved. But, even if it were all possible, for a camera company to make one of those, it would likely cost about what an M9 costs and they'd probably sell about one of them, to me, if I could afford it. So, its a fantasy, which is different than a dream. And I'm damned happy with the three cameras I DO own and shoot with, so its far from important.
At the moment I am dreaming of the GF3 which I have ordered together with the 14mm and the 20mm. I feel some insecurity, if the 25mm were the better choice instead of the 20mm, because it is the better lens and lies exactly between the 14mm and the 45mm. But these kind of doubts won't ever leave me, because I am a not only a photographer, but also a gear head.
I think my dream camera would be an E-PL3 with some sort of grip. As much as I'd like to buy an E-P3, I think I'd enjoy the E-PL3 with a grip better, mainly being a smidge smaller and tilt screen. Honestly, I like the E-PL2 form factor out of all the PEN's, even over my E-P1. As of late, I've been having too many issues with the E-P1.
Lots of choices right now...no perfect camera for me(yet!)