The Goddess

One thing that most people consider a disctinctive feature of Paganism is the Goddess. Granted, many world religions have goddesses, but, in Paganism, the Goddess is revered on equal, or elevated, terms as God. The prescence of the Goddess is worrisome for Christians because Christianity is extremely patriarchal. Only now, with the popularity of The DaVinci Code, are mainstream Christians becoming aware of the feminine prescence within their own religion.
The general consensus among Pagans is: ask 5 Pagans and you'll get 6 answers. Every Pagan has their own take on the God/Goddess concept. I personally acknowledge both a God and a Goddess, with a focus on the Goddess. I focus on the Goddess because, being raised Christian, this divine feminine was a prescence that was entirely denied me growing up.
Other Pagans, particularly those with a feminist outlook, acknowledge only the Goddess. I must admit that I don't know much about the feminist approach to Paganism. The impression I get is that the need is felt to establish a matriarchal approach to redress the male/female balance, which the patriarchal society we live in has thrown off.
The next issue of course is: what Goddess/God to acknowledge. Again, there are many opinions on this. Some acknowledge a generic Goddess and God, using whichever names are appropriate to the work being done. Other Pagans, adopt a particular deity that they resonate with. Since Paganism is about the individual quest for spritual expression, there is no right or wrong about this.