Here I attempt to describe a few of the words used to describe people who are on or around the atheism/theism border.
The first one that of course everyone has heard of is agnosticism. Usually, an agnostic is defined as someone who doesn't know whether a god exists, thinks that it is impossible to know, or thinks the very idea is meaningless. This description fits almost anyone outside of religion, so an agnostic can really be anyone who has taken a liking to the word. That said, most agnostics I've seen tend to be very similar to atheists, aside from a few distinctions that are a little too subtle for me to understand. If you asked me, it is impossible to absolutely know anything outside of math and logic, but I am entirely unsure of whether that qualifies me as an agnostic.
I must also mention that atheists tend to negatively stereotype agnostics as fence-sitters who simply don't have the courage to admit that gods are as unlikely as fairies. That is, atheists seem to think agnostics actually give equal weight to the two possibilities of god and no-god. This stereotype simply has not been reflected in my experience; most agnostics seem to hate the stereotype. But I've reason to believe that it's reflected in at least some agnostics out there. What did I say earlier about straw men in large debates?
The word "deism" usually refers to belief in a god who does not participate in the world. The deist might be persuaded by one or more of the arguments for God's existence, but not persuaded by arguments from revelation or miracles. In other words, the Deist accepts the notion of a God who created the universe, but rejects the notion of a God who constantly meddles with humans. This might be the most likely position for a skeptical theist to take, since there are obvious parallels between so-called "miracles" and paranormal claims.
Pantheism refers to the belief that God is the universe, or the nature of the universe, or something along those lines. There is an argument for God that goes like, "The universe must have an ultimate cause, an uncaused cause, and we call that God." One of the counter-arguments is, "Why can't the universe itself be the uncaused cause, or "God" as you called it?" I think pantheists take this argument seriously. Arguably, pantheists have redefined the word "god" and are talking about a completely different concept. I don't see many pantheists around, but it's often said that Einstein was a famous case. All those famous quotes, such as, "God does not play dice," should be interpreted accordingly.
Those are the three major categories, but there are a lot of other terms being thrown around, and a lot of people who fit under none of them. I once knew a guy who believed that every human's consciousness was a small piece of God's consciousness. What in the world would I call that? I prefer to refer to the entire group collectively as freethinkers, which means anyone who has rejected organized religion.