The NFL and the players union agreed on a pair of rule changes:

The trade deadline will now be after Week 8 of the season instead of Week 6,
while teams will be allowed to activate one player off injured reserve during
the regular season.
From link

Activating a player off injured reserve is a pretty significant change. That would have let us IR Bob Sanders a few years ago instead of tying up a roster spot for him all year while we hoped he would heal.