There is a really good Wikipedia article on the evolution of Bohemian style:
http://www.en.wikipedia.org/wiki/Bohemian_style
I have been thinking about this concept and style definition for a while and found this helpful - that our definition of boho may depend on what generation we are from. It is sort of become anything outside of mainstream in a way. The first folks to "go their own way" such as women wearing mens trousers or bobbing their hair , or letting hair flow freely.
The tumbler images seem to fit the Luxe Grunge concept of boho (sort of a subset in a way). There could also be Hippie Chic or even the Steampunk/Goth looks under the boho umbrella if you follow the concept laid out by Wiki contributor. Makes sense to me.
The Luxe Grunge seems like very updated takes on super casual - everything is fabulous fabrics, clean silhouettes and not too fussy. You do get the occasional Olsen-girl type who combines Luxe Grunge with Hippie Chic (which translates to ALGO in my opinion).