igary.
those leica pictures are third-hand postings. we can't be sure it's leica, we don't know how the film was processed and whether the digital scans came from film or print and what device was used. we also don't know what image processing software and techniques were applied to the jpeg resizing.
all i can tell you is that the 3 leica lenses i own never, ever produce anything but top quality bokeh. in fact, even my non-leica lenses (all carefully chosen) never let me down in this regard, with the exception of the tamron 90mm macro. another horrible performer was a nikon lens i borrowed a few years ago.
if you wish to satisfy your curiosity, go rent a leica for a day and do you own comparison. better yet, just buy one ebay and play with it for a year--you will recover every penny if you choose to sell it. that's actually what i did, except i was so impressed, i bought a superior leica camera once the experiment was over.
lots of people yack and yack about this and that on the internet forums, but hardly any of them actually try out the competition and they all invariably quote "specs" (the way someone would talk about aplifier watts) to justify their opinions. i have a canon, a minolta (TLR), a contax, 2 leicas (rangefinder and SLR), a zorki, a pentax and just recently acquired a bessa. if you go back a few years, i owned the olympus e-10 digital. i even shot a session with a nikon digital a few weeks ago as a favour to a friend. hence, most of my impressions are to do with first-hand experience and i have to say it's the only way for an obsessive-compulsive to avoid having questions of quality hanging over him for ever.
vuk.