I don't really care too much about current fashion. However, I will fall prey to trends now and then, so I don't feel like I stick out as much anymore. The most recent one was after moving out to MT, was wearing of ski hats. I do actually like them quite a bit. I would never have started wearing them though had it not been for most people out here doing so, as such it is seen as a trend.
I won't pick up on fashion trends though that do not fit my personality, as I don't like misrepresenting myself. I have found confort in wearing hoodies, and cargo pants for several years now. Physical confort is a major factor for me in wearing something (I like to feel "confined/hidden" in a way), and if that is not their I will not wear it.
So pretty much, I would say current fashion influences what I wear around 30% of my overall clothing decisions.