I honestly don't know.
I still believe most of what I believed when I identified as a Pagan. I still love nature, trees and rocks, folk-tales and firelight, the moon and the stars and the nurturing darkness, the sunlight on the water.
My cosmology hasn't changed that much - gods and goddesses have been reclassified as wights or loas or genii loci (some more friendly than others), and the sea of limitless light has acquired more personality than I believed was possible.
The jury is still out on reincarnation, though I certainly believe in apocatastasis (the eventual metanoia of everyone).
I sort of believed in the Fall as a Pagan, so no change there - but I understand it as a shift in consciousness where we saw ourselves as discrete beings separate from the Divine, losing our sense that "we live, move and have our being" in the Divine. Interestingly, the Wikipedia entry says that it was a "transition from a state of innocence to a state of knowing only dualities" - so it makes sense to try to view things in a Taoist manner.
I wrestled with the problem of evil as a Pagan, and came to some sort of conclusion, but didn't know what could be done to resolve it. Now I believe that the Divine is working with and through us to resolve the problem (in Judaism, the idea of Tikkun Olam; in the words of St Theresa of Avila, "Christ has no hands but you.")
I'm not a Christian as such, because I can't sign up to the Nicene Creed or accept the sole authority of the Church or the Bible. And I think the Trinity is a useful model, but not the whole picture.
I believe all traditions are valid paths to the Divine (well I sort of believed that as a Pagan, but now I feel it). I guess all that makes me a Unitarian... but one with both Pagan and Christian roots, and a strong interest in other traditions.
And the Christian habit of equating darkness with evil really gets my goat. Darkness can be nurturing and 'female' and yin; it's the hidden processes in the earth. It may be the absence of light, but it's not evil. This is not just a matter of symbolism, it's about what you do with the unconscious content of your psyche, whether you slay it or seek to transform it.
I am massively grateful to my Orthodox and Catholic friends for helping me to understand the mystical side of Christianity, and some of the important theological concepts of it. And I am full of admiration for all the LGBT Christians out there, struggling on faithfully in their love for Christ against massive discrimination.
I'm also deeply grateful to my Pagan friends for being patient with me while I wrestled with this, and for their helpful comments and suggestions, especially Trystn and Cat.
But when it comes right down to it, it's the Tao Te Ching that makes the most sense to me, and illuminates the meaning of the other traditions.