It's fantastic that Musk is ready to dive back into the hyperloop plan first hand, and push it forward at a faster rate. However, it stands to complicate the issue for the other three companies that have taken on the project and invested quite an amount of time and money thus far.
Musk shared a substantial white paper on the topic in 2013. He had drafted it with his team at Space Exploration Technologies Corp. At the time, Musk made it clear that the plans were to function as a free starting point for any company or individuals that had the wherewithal to attempt to move it forward. He shared on a conference call:
"I don't have any plan to execute because I must remain focused on SpaceX and Tesla."
In the simplest of terms, the hyperloop is a future form of transportation, which relies on a pressurized vacuum tube to move a suspended pod through at incredible speeds. Due to the lack of air resistance and friction, Musk's plan showed the potential for travel over 700 miles per hour.