A good summary report by William P. Doyle, Director of Permits, Scheduling & Compliance Office of the Federal Coordinator was submitted to FERC last week (LINK).
This report provides a good summary of the various possible Alaska Gas Pipeline Projects, although it states that
There is a very low probability that all five projects may be constructed. It is more likely that one interstate and one in state natural gas pipeline will be constructed.
Below, a figure from the the report showing all the possible projects: (Click on it for detail)