vintage design style logo

You'll have to agree with me that vintage style is in trend these days. Not many logos are done in a pure retro design style, but more logos seem to adopt elements or characteristics of the vintage trend. I've made a selection of the best logo designs that use vintage elements, posted here at the LogoMix gallery and I tried to identify what are the main characteristics used to achieve or to imprint a vintage feel to a logo design. Here is what I've observed. Feel free to approve or disapprove with my list of elements, or to add your own.