I think it's an N thing. I know Ns of all type that are into philosophy. In fact, I'd say the INTJs I know are the least into philosophy of all the N types I know. I doubt this is a general trend, though.
I study philosophy at uni, and I'd say that the majority of people studying it are introverts. My philosophy modules are the one's in which I am most conscious of people who stand out for their introversion, so I think it also contains a lot of polar introverts; people who are totally content by themselves and seem fairly introspective and caught up in their own thoughts a lot of the time. My class is also predominantly N's, which is to be expected I suppose. In terms of T/F, I'd say mostly T, but a few of us are F's. It's actually difficult in an academic context to determine T/F; I'm sure some people in my class would presume I was a T, I know in the past people have thought that when they've only seen me in discussions. As for J/P.. hmmm, probably mostly P's, although interestingly the J's we have are J squared.
I think INTP's are the type who would view philosophy most favourably; they're reflective, ideas orientated, and a P so prepared to engage with a variety of ideas. It's funny, although INTJ's definitely demonstrate some interest in philosophy, I see very few of them who love it; my younger (INTJ) brother told me he'd find my course infuriating, since so many of the ideas are just *wrong* (wry smile). I actually think a lot of the philosophy I study is totally illogical and nonsensical, and various philosophers contradict eachother etc. so of course you will be exposed to ideas in the discipline which you disagree with. I derive enjoyment from discussing ideas I think are rubbish though, whereas J types might be inclined to see it as a waste of time, or, in actual fact, irritating.