I've used M8s, loved the glass (of course), could never really get used to the rangefinder for landscape (what I do, but in the Eastern US, it's NOT always at infinity focus - a lot of "landscape" here is really halfway between landscape and macro). I'm still looking for something that will give me the image quality of my D3x without the weight (both body/lens weight, and it takes a lighter tripod). The M9 is both too expensive and not close-focusing enough (plus it's really hard to focus a rangefinder accurately at 1 meter). I've been using a GH2 as a travel camera for the past year, and it's "almost there", but doesn't have the dynamic range I want - DR is a bigger issue than resolution (and the single-dial controls are a bit clunky - I like to have aperture plus either shutter speed or exposure compensation right at hand). I have an NEX-7 body on order, and I'm hoping this'll be the solution - a lot of control, plus a sensor with supposedly very good characteristics. I'm a little worried about the lenses, but I'm guessing the Sony G/Zeiss situation will improve in the next year, plus there are always adapters - I think the peaking will work better than a rangefinder for what I do.
On a related note, a lens category I haven't seen in some time (and I mourn the passing of - correct me if I'm wrong) is the modest-sized, not terribly fast, but HIGH-QUALITY zoom. Nikon in particular used to produce "super kit" lenses that were not f2.8 (they were in the range of f3.5-f4.5), and had fairly modest zoom ranges, but they had much better optical quality and somewhat better maximum aperture than regular kit 18-55s (or their film equivalent, the 28-85). They were at least twice the price of a kit lens, but only ~20% bigger, and, when stopped down to f5.6 or f8, their image quality rivaled pro zooms. I'd love to see Sony make a "SEL 18-70 f3.3-4.5G" that complements the NEX-7 better than the 18-55 coke bottle. I think a lot of NEX-7 buyers would pay $600-$700 for that lens (and it could be sold with the body in a $1599 kit). I am always shooting between f5.6 and f13 (stop down any further, and diffraction rears it's ugly head) anyway, so the lack of f2.8 would be made up for by the size and weight of the lens.
A camera that I'd LOVE to see, but I suspect will be too specialized to get made (Nikon once played with a prototype, from various indications (they called it MX format in some leaked literature)) is a Medium-Format NEX-7... It would look like a Mamiya 7 with a big ol' screen on the back (plus a NEX-7 grade or better EVF) and a couple of extra dials, and have a 40+ MP 645 sized sensor. Focus would either be Contrast AF (with manual override) or purely manual, with magnification and peaking to help. One really off the wall possibility would be electronically controlled sensor tilts and shifts, which should be possible in a Mamiya 7 sized body with a 645 sized sensor. I think this type of camera would find a niche among landscape photographers, as well as among studio folks...