It is characteristized by a strong emphasis on social justice with a focus on promoting values such as compassion, justice, mercy, and tolerance, often through political activism. Though prominent, the movement is by no means the only significant movement of progressive thought among Christians.
The concerns of feminism are also a major influence on the movement, as expressed in feminist and womanist theologies. Currently the LGBTQ community's concerns of acceptance are a focus point for the group.
What is problematic is most progressive Christians are moral relativists. They are generally loose on their views of theology. They hold onto Jesus' love but try to make Jesus more palettable for the culture. They believe that Christianity needs to progress and change and adjust its morals and beliefs to survive to the times.
In principle, it consists of evolutionary thinking and deconstructs; critically dismantling and opposing traditional theology, language, and logic of literary text, expositing nihilism and frivolous skepticism.
Reference: Wikipedia, Britannica