The NFL announced today that they are extending the number of players on each team's practice squad from eight players to ten. This is pretty big news, especially for the players as it allows 64 more players to be employed by a team come the regular season.
In addition to the extra two players, they changed the rules of how much experience those two players can have to be eligible for the squad. The new rule states the extra two players can have up to 32 games on an active roster over their first two seasons and still be eligible for the practice squad. So, basically any 2012 or 2013 rookies are now eligible to fill those two additional practice squad positions.
The other eight players on the practice squad will still be under the old eligibility rule which allows for no more than eight games on an active NFL roster.
Another new rule in place says if a player spends less than six games of the season on a team's practice squad, it doesn't count against their total practice squad seasons. This is key because players are only allowed three full seasons of practice squad eligibility.
Teams routinely pluck members of the practice squad for the active roster as injury replacements and such, so the more practice squad players the better. It allows more opportunities for the players and more options for the teams.