Over at Creed, Code, Cult, there is a new post (LINK) briefly discussing the core differences between Catholics and Protestants. People on each side of the fence need to know both their own position as well as the position of those on the other side, otherwise dialogue will never go anywhere. When each side defines key terms very differently, it does no good to simply quote verses, since each side is reading them with their own lens.
There is also an good discussion going on in the comments between me ("Nick") and "Eric," as well as a few others. The other comments are not really on topic, so if you don't have the time, just skim over them (e.g. the person posting by the name "Faith" is going off on his own tangents).