The latest in a number of articles about the recent awards by NASA's Commercial Crew Development (CCDev) program comes from Jeff Foust writing for The Space Review. Jeff also hosts the Space Politics blog.
NASA, in its assessment of the proposals, showed a clear preference for complete transportation systems rather than proposed subsystems that "failed to show solid commitments from element providers." A number of proposals were eliminated based on that assessment, including Paragon Space Development Corporation, which won one of the five first-round CCDev awards last year to work on a life support system for crewed spacecraft.
Other companies were cut during the assessment for other reasons, from having major, glaring weaknesses to failing to follow the instructions in the announcement. Also getting cut at this stage was a proposal from USA, the Boeing-Lockheed Martin joint venture that handles shuttle operations, to study commercial operations of part of the shuttle fleet beyond the scheduled retirement of the orbiters later this year. Without discussing the specifics of the proposal, the NASA source selection document states that it "did not fall within the scope or intent of the CCDev 2 effort," and as a result USA withdrew its proposal last month.