Originally posted by spinach that the "point" of mirrorless is to be slimmer than a DSLR. The principal point of mirrorless is to remove the mirror.
And Why,....?
It's because it's cheaper to make a mirrorless then it is to make a traditional DSLR.
It has nothing to do with the size of the lightbox, the flange distance, the mount, it's all about how much money is spent producing the product.
There's no reason to make it slimmer - if you want a slimmer camera, buy a Q, if you want a slimmer camera and to use K-mount lenses, buy a Q and the K-toQ adaptor. If you want a viewfinder, buy a K3.
I think what a lot of people are forgetting, is that between the Q, K-MILC, K-DSLR and 645's, Pentax has covered nearly every aspect of photography.
( yes, some will moan about FF, get over it, 95+% of people can't tell the difference between shot on APS-c and FF )
I'd even argue that the 'success' of the K-01 is the real reason the EOS-M even exists at all.
If Pentax spent more time on developing the firmware to match what people want to use the cameras for, more people here would see what I see on film sets - DoP's with more money then talent, who pick up my K-01 and wonder "why they didn't know it existed and why are it's stills so good?"
If you knew the number of times in the last six months where I've been asked "Where can I get one?".....