A writing teacher of mine once said that beginning fiction writers tend to write in the first person. As they grow, they "graduate" to writing in third.
Like the honor student I used to be, I took this as a task to be fulfilled. I was writing in first person in those days, for god's sake, which meant I was not a mature writer. How embarrassing to be revealed in this manner, when I'd thought my narrators were ever so sophisticated! When I did start using third, and managing not to screw it up completely, I felt I had made it to a new level of respectability. Writing in third meant I was in control, surveying the whole story from a height of my choosing. At least in theory, I was able to incorporate the sweep and scope of the great 19th century novels, the likes of which I didn't particularly aspire to write, but could have. Maybe. The point is, the third-person writer has authority. The first-person writer not only acknowledges her subjectivity but flaunts it, or worse, hides behind it, afraid to deliver any bigger truths than one individual's epiphanies.
However, I have since regressed. My second novel and the new short story I'm attempting to write are both in first. What has happened? All of a sudden I'm finding third person far more limiting. True, you can justify traveling among places and times and consciousnesses in ways you can't do in first--in a realistic first, I might add. But I can't let go of the notion that someone is always telling the story. She may be all but effaced behind the opaque screen of minimalism, or you may have the chatty, confidential "I" of much 19th century fiction, who does not sense his perspective as limited at all. In any case, there is a narrating consciousness. Some may simply decide that's the author's consciousness, with no intervening figure between it and the reader, but I somehow can't see that. To me, the narrating voice is always created, through the act of writing itself; it's artificial, which I don't mean in a negative way. So I feel like I have to understand that voice, and who it's coming from. In other words, third keeps blending into first for me anyway, so why not save a step and just do first?
It may be that first limits you in terms of saying what other characters are really thinking, and keeps you from being in two or more places or times at once. On the other hand, first gives you a tremendous amount of internal latitude. It seems to me it's much easier to justify flashbacks, for instance, in first. We suddenly remember stuff all the time, and having the memory can be part of the story, rather than (god forbid) a sort of pat psychological underpinning for some character. You can also just stop the story and muse (engagingly, of course) on the narrator's pet obsessions: Why does my father insist on wearing those glasses? How can my best friend believe in ghosts? Did the world really exist before I came into it? (Try thinking about that through the mind of a fictional character!)
Anyway, I'm finding there's lots of terrain to explore in the first-person point of view. But I wouldn't rule out authorial immaturity, either.