USCIS has had the $500,000 for TEA or rural investments and $1 Million for all other investments and has not indicated any change, even in the most recent policy memorandum. It appears unlikely that the minimum would rise. If it were to change, however, there would probably be opportunity for EB-5 stakeholders (attorney's Regional Center owners, etc.) to provide comments to such a change.
There is always the possibility that the U.S. Congress with immigration reform may increase the minimum amount for the EB-5 investment requirement. However, there is no real indication from the USCIS that they will agree to the increased minimum requirement.