From what I've read, what is supposed to happen is that they be held in Qatar for at least a year under watch of the Qatar government.
There are statements from Qatar that the 5 prisoners are free to travel within the Persian Gulf Emirate and that U.S. officals are not allowed to monitor them. How much of this is true, I don't know.
There have supposedly been incidents in the past where we have relied on other countries to restrict and keep watch on threats to the U.S. and these threats traveled out of said country multiple times before being caught....
But, I can bet that those Taliban members that met with U.S. special forces during the trade-off are being watched carefully.