I've been a little slow to respond here, but also wanted to thank Peter for the info! It's so nice to have an abbreviated, single source to compare lenses. Very helpful information!
So a "tabbed" Summicron is just referring to the 'crons from 80-95(?) that had focus ring tabs? I saw a site once that referenced the expected market price for certain lenses, etc but I can't seem to find it now (when I need it of course). Any ideas?