+1 catyrpelius
I consider the true hipsters the ones who are trying too hard. Wearing non-prescription glasses (or worse, without lenses). The super tight jeans, the t-shirts that are too tight and layered with a horribly ugly -and more importantly very used- cardigan. Scarves that aren't seasonal or traditionally worn by men. Listening to music no one has ever heard of so you can say you listen to bands no one has ever heard of.
The main difference is trying to be ironic and that comes from the look of trying too hard to be different just to be different.
I could be considered a bit of a hipster as I smoke a pipe (not ironically), dress nicer than most of my peers (button ups, sweaters, ankle boots, chinos, ties, vests, etc.), I like flat caps and listen to music most people have never heard of (metal) ... but I don't talk about it nor do I act pretentiously. Hipster and Bohemian meet ironically and produce what we generally loathe and consider "hipster."
Buuuuut, they have also created a market that I am thankful for: better restaurants with creative menus, better coffees, better beers and making old stuff cool again.
They are a gift and a curse.